HOW LONG SHOULD I KEEP WITNESSING TO THE SAME PERSON?
by Shawn Brasseaux
“How does one determine to be patient and to keep witnessing to someone, or to avoid him or her altogether?” What an excellent question! I am sure many have often wondered about the same matter, so we need to look and see God’s advice on the subject. We will see, “For what saith the Scriptures?”
The time you should spend witnessing to one person is not always a “clear-cut” issue. Many varying factors and cues are involved, and it would be best to keep them in mind; we will consider how to go about handling some of these issues. First, we need to look at Bible verses that show us how saints witnessed in the Bible. Then, we will look at some of my specific witnessing experiences for illustration.
1. LOOK FOR CUES THAT INDICATE THE OTHER PERSON’S INTEREST, INDIFFERENCE, OR INSOLENCE.
The following are indications that you are probably getting nowhere with the person to whom you are witnessing: overt mocking of the Bible; scornful laughs; numerous complex, trick, or trivial questions; angry demeanor; name-calling; extensive rambles/rants; harsh tone of voice (or shouting); tantrum-throwing and other immature behavior; silence; their repeated mentioning of the same erroneous teachings, as if you did not already address them with Scripture; hands put up as if refusal to listen; phrases uttered such as “Respect my beliefs,” “Leave me alone,” “Let us agree to disagree,” “You’ll never convince me,” et cetera.
Telecommunications conversations (emails, text/instant messages, online discussion boards, website forums, et cetera) are very tricky to evaluate. While you cannot discern tone of voice or facial expressions that further communicate the emotional and spiritual state of the other person, you can watch out for chief signs of fruitless discussions—sarcasm; numerous sidetracked comments (remarks unrelated to the topic at hand); continual focus on the same topics (asking the same question over and over, although rephrased, even after you answered the original question with verses); EXTENSIVE ALL CAPS; and numerous exclamation points. These are online versions of shouting and arguing, and that is not what we are here to do as Christians. Time to move on when you see a lot of these types of online behavior!
Concerning short-term. The more negative behavior that you observe in any single witnessing episode, the greater the need to politely end the conversation as soon as possible. The encounter may even escalate to physical contact at some point, so you want to try to avoid reaching that level. Many negative cues, especially in one particular day, is a clear sign that you are wasting your time with the individual. Time to move on!
Regarding long-term—a course of days, weeks, or months. You should tolerate occasional opposition from one particular person. But again, be reasonable. If after many instances of you discussing the Bible with them, and they are persistent in that type of behavior, that is a clue. You need to step back and refrain from having any further Bible discussions with them. Time to move on!
By the way, to determine whether patience or distance is needed, you need to also think about the entire situation, as well as any previous conversations with that individual. If you know them, consider their religious background (denomination or world religion), any religious higher education (seminary or Bible college), et cetera. If they are highly educated, they are less likely to listen than common people would listen. They believe they have “already figured everything out.” What I have discovered is that the average seminarian or Bible-college graduate has no intention of thinking outside of his or her “box of academia.” I have talked to them before, but I do not engage in prolonged discussions unless their attitude demonstrate they want to have intelligent Bible discussions.
Consider these Scriptural tips I always keep in mind when witnessing to others.
After the Lord Jesus preached to all of Israel for three years, the viciousness of the naysayers grew more intense. His own people became more and more opposed to Him. At the beginning of His earthly ministry, in His hometown of Nazareth, Jesus has just read some of the book of Isaiah in the synagogue service, and then He begins to reprimand them for their unbelief in Him. We read: “ And all they in the synagogue, when they heard these things, were filled with wrath,  And rose up, and thrust him out of the city, and led him unto the brow of the hill whereon their city was built, that they might cast him down headlong.  But he passing through the midst of them went his way” (Luke 4:28-30). When the audience wanted to throw Him headfirst off of a cliff, it was His cue to leave. Jesus somehow sneaked away and avoided death! He did not provoke them any further but left the scene.
In Matthew 12:14, about halfway into His ministry, the Bible says the Pharisees held a council how they might destroy Jesus. In Matthew 13:24, they began to accuse Jesus of being possessed by the Devil! By studying Matthew 12:15-21, Matthew 16:20, Matthew 23:34-39, et cetera, we can see that Jesus Christ began to gradually withdraw from a national ministry. When He had preached to all of the cities of nation Israel, so that they would all be without excuse, He then began ministering to the few Jews who had heard and believed His words. He increasingly preached to and taught those who did want to receive His words. Jesus just gave the rest of Israel over to spiritual ignorance. He did this by introducing His parables, stories that would only confuse those who had refused to hear and believe God’s plain Word during the many months prior (Matthew 13:13-15). He gave only the believers the ability to understand what the parables meant.
In John chapter 8, toward the end of His ministry, Jesus delivered an extensive rebuke to the Pharisees. As He exposed more and more of their unbelief, they became more insulting toward Him. Finally, they became very belligerent. They began to pick up stones to throw at Him, “but Jesus hid himself, and went out of the temple, going through the midst of them, and so passed by” (verse 59). Jesus knew not to engage in further contact with them. It was time to move on and He did! He told them the truth, they got mad, and when He saw they were bent on behaving irrationally, He left!
Once Jesus recognized they would not hear Him, He moved on to those who did want to hear God’s truth. Our Lord was very wise. He knew that He had a lot to do and say and only three short years to get it all done! He could not dilly-dally addressing every single point posed by every single critic. We should learn from how He conducted His ministry. Like Jesus, we want have only a limited amount of time and energy to conduct our earthly ministry. We need to spend more time teaching God’s Word rightly divided and less time simply saying “no” to every false teaching and every Bible critic.
When commissioning Israel’s 12 apostles, Jesus said: “ And into whatsoever city or town ye shall enter, enquire who in it is worthy; and there abide till ye go thence.  And when ye come into an house, salute it.  And if the house be worthy, let your peace come upon it: but if it be not worthy, let your peace return to you.  And whosoever shall not receive you, nor hear your words, when ye depart out of that house or city, shake off the dust of your feet.  Verily I say unto you, It shall be more tolerable for the land of Sodom and Gomorrha in the day of judgment, than for that city” (Matthew 10:11-15). If the apostles were not welcomed into a house or city, Jesus said they were to leave it. They were to speak what they needed to say, and then leave when opposition came. They were not to waste time forcing the household or city to listen to them.
When the Apostle Paul had preached Jesus Christ to the Jews in Damascus long enough, the unbelieving Jews plotted his murder—the Apostle’s ministry companions had enough sense to quietly sneak him out of town (Acts 9:20-25)! When the unbelieving Jews wanted to kill Paul and Barnabas by stoning, the Apostles quickly left the city (Acts 14:1-7)! In Acts 17:10, in Thessalonica, the unbelieving Jews were plotting against Paul and Silas—they had to leave town hurriedly here too! When the pagans in Athens laughed at Paul’s sermon, he left them alone in their ignorance (Acts 17:33)! When the unbelieving Jews refused to hear Paul preach Jesus Christ in the synagogue at Corinth, he left them in their spiritual ignorance and went minister to people next-door (Acts 18:1-7)! In Ephesus, Paul spent three months preaching in the synagogue (Acts 19:8). The Bible says in verse 9, “But when divers were hardened, and believed not, but spake evil of that way before the multitude, he departed from them, and separated the disciples, disputing daily in the school of one Tyrannus.” Once Paul recognized a persistent, defiant attitude in the Bible critics, it was time for him to move on! When they continued to “speak evil of that way,” Paul knew that he was wasting his time, and he began to teach believers. The point is that Paul, like Jesus Christ, used his time wisely. He travelled extensively throughout the then-known world, reaching as many people as he could, and eventually leaving those alone whose hearts had become increasingly hardened to God’s Word.
We find an interesting passage in this regard, 1 Timothy 1:18-20: “ This charge I commit unto thee, son Timothy, according to the prophecies which went before on thee, that thou by them mightest war a good warfare;  Holding faith, and a good conscience; which some having put away concerning faith have made shipwreck:  Of whom is Hymenaeus and Alexander; whom I have delivered unto Satan, that they may learn not to blaspheme.” These people—evidently Christians (!)—the Apostle Paul said he “delivered unto Satan” because they were blaspheming (in the context, embracing false doctrine and probably teaching it, too). Paul gave up these men to greater error! Again, we should not force people to do anything or believe anything. Free will! Free will! Free will!
One of the qualities of a bishop (church leader, elder) was, “Holding fast the faithful word as he hath been taught, that he may be able by sound doctrine both to exhort and to convince the gainsayers” (Titus 1:9). A church leader—yes, every Christian—should confront the opposition, the unbelievers and the Bible critics. But, this should be done with wisdom and prudence. Friends, after an extended period of time, it is time to move on!
Let us look at various verses from Proverbs.
“Go from the presence of a foolish man, when thou perceivest not in him the lips of knowledge” (Proverbs 14:7). “The beginning of strife is as when one letteth out water: therefore leave off contention, before it be meddled with” (Proverbs 17:14). As soon as you recognize that someone enjoys the deception they are in, that they are openly resistant to the truth you are sharing, go from their presence. As soon as you see they are “contending” (arguing), you need to move on… and quick. If you stay, you just might find yourself in a physical brawl!
Now, Proverbs 22:10: “Cast out the scorner, and contention shall go out; yea, strife and reproach shall cease.” Those who want to mock, if you get away from them, contention (arguments, disagreements) will leave you. There will be no strife (fighting, trouble) and no reproach (criticism, rebuke). When you observe mocking, criticism, arguments, fighting, et cetera, it is time for you to move on, friend! Do not waste time with the person.
Next, Proverbs 23:9: “Speak not in the ears of a fool: for he will despise the wisdom of thy words.” There comes a point in time when you recognize a fool. It is someone who has an objection to every Bible verse you quote and every Bible truth you share with them. Time is needed to recognize the pattern, but you eventually learn they are just willfully ignorant. They do not want God’s precious Word. They want their religious traditions, their scientific data, et cetera. Give them what they want. Quit talking and leave!
And Proverbs 29:9: “If a wise man contendeth with a foolish man, whether he rage or laugh, there is no rest.” The “foolish man” here is the Bible rejecter, the one who refuses to listen to and believe God’s wisdom. Whether he grows angry or he laughs, neither action will cease. The Bible believer is to leave this person alone. Let them enjoy the spiritual ignorance they so joyfully embrace (Romans 1:18-32)!
When dealing with any anti-Bible person, whether denominationalist, or world religionist, or atheist/evolutionist, et cetera, the wise Christian soldier should always consider Proverbs 26:4-5: “ Answer not a fool according to his folly, lest thou also be like unto him.  Answer a fool according to his folly, lest he be wise in his own conceit.” God is a God of freedom: never are we to take away anyone’s free will. Sometimes, we are to answer our critics; other times, we should not waste our breath. While most do not want to know God’s truth, let us be mindful of those few who are seeking it. May we be as polite and patient as possible when the conversation is conducive to learning (worthwhile questions). May we respectfully withdraw when intelligent discussions are deemed impossible (name-calling, sarcasm, tantrums, et cetera).
2. DO NOT “CLOSE THE DOOR ON THEM” COMPLETELY (UNLESS UNDER SPECIAL CIRCUMSTANCES).
As long as someone is not deliberately trying to confuse you and convert you to a cult, or has not threatened you with physical violence, you do not have to permanently cut off all contact with them. Remember, you are not trying to make enemies, but if they do see you as an enemy because of your stand on sound Bible doctrine, you can do nothing more about it. Pray for them and love them, but you will not convince them if they do not want to hear the verses. Do not force yourself onto them but do not completely isolate yourself from them, either. Friend, there must be a balance. In fact, with family members, coworkers, close friends, classmates, et cetera, avoiding them entirely is usually impossible. You can still visit them and talk with them, but do not discuss the Bible unless they ask. If it is an emergency like sick-beds or death-beds, you should speak up about the Scriptures, but do so in the spirit of love and meekness. Let me give you a few examples of how I approach such people.
A Christian relative cursed me out because of my stand on Bible doctrine, so I avoid that particular topic (Bible versions) with him now. In the years since he fussed me, he has approached me a few times for Bible understanding. Imagine my shock when he even asked me to write some Bible study notes so he could use to teach in his denominational church! With him, I make a few brief instances to Scripture in conversation, but nothing too deep. When he asks me about how my ministry is going, then I mention some Bible verses or themes. But, even to this day, I try to limit myself to a few minutes of Bible discussion with him. He is a saved man, which is a start, but it is up to him to grow in the Bible. He seems to be a little more open to sound doctrine (dispensational Bible study), so the more receptive he is (the less “no’s” I hear from him), the more I talk with him about Scripture the next time around. If nothing else, he can see the lifestyle I live, and it just may peak his interest one day to learn more about what I believe.
Over the years, at funerals or sick-beds, my parents and I have talked with lost relatives about the Gospel of the Grace of God. When my paternal grandmother died last year, I gave her eulogy, mainly to give a Gospel invitation to all of our unsaved relatives and family friends. It was a simple plan of salvation message, spoken with respect and solemnity, and no one could misunderstand unless they wanted to misunderstand it. While I could judge that the vast majority of my religious family was indifferent concerning the message (the room was deathly silent after I finished!), they nevertheless heard the Gospel of God’s Grace and are thus without excuse to this day. Not one person—including the angry Roman Catholic deacon officiating the service—left that funeral home without a knowledge of how to be saved from their sins through the finished crosswork of Jesus Christ. Whether they decided to trust Him or not, that is out of my hands. I have spoken to them since, but not much about the Bible and nothing about the Gospel. At this point, I would be forcing it on them. They need to come to me now if they want to talk. They see the Bible resources I post on Facebook, Twitter, YouTube, et cetera, and it is their decision.
Now to pastors, seminarians, priests, Bible teachers, et cetera, with whom I have dealt these past several years. If they were largely argumentative, sarcastic, disrespectful, and showed me that they were not Bible believers but Bible doubters and scoffers, I no longer approach any of them or seek them out. They will have to come to me if they want to discuss the Scriptures. I have no reason to contact them. If any of them want to contact me, they know how to reach me. Depending on how much foolishness they displayed in the past, and the nature of their current discussion, I may consider replying. Otherwise, to keep the peace, I have left them alone and given them over to what they want. It keeps their flesh from being exploited and it keeps my flesh from being exploited. I treat them especially different than common church members because congregants and parishioners are often less prideful than church leaders.
Recently, I spoke with a religious woman no more than five minutes about the Bible. No matter what I said, she kept repeating the same errors and defending the same teaching she had heard all her life. When it became apparent to me that she was not going to change her mind, that she would not submit to Scriptural and historical facts, I left off the conversation. I told her that the discussion was fruitless and thus not worth continuing. I recognized that she was trying to convert me to her denomination. She did not want to hear the Gospel and be saved from her sins. She just wanted me to agree with her church tradition. I finally had to let her go. I did not give her any of my contact information. I have better things to do with my time than speak to someone who has no eye to see, no ear to hear, and no heart to believe God’s truth.
Some years ago, a professing Christian used to argue with me online about Bible truths. I simply disregarded him, and we broke off contact for a few years. A few years ago, and ever since, he has emailed me with Bible questions (especially asking me about some false teaching that he needed rescuing from!). While he certainly has other doctrinal hang-ups, he seems to be more “straightened out” doctrinally now, and open to being taught. I share Bible verses with him every chance I get. He has never argued since.
A man who was confused about legalism once emailed me, explaining how he was about to give up on Christianity. He was at his wits’ end with all of the perplexity! After I responded to his email, he was silent for four months. I wondered if I wasted my time with all those dozens of pages of studies I wrote just for him. Then, he emailed me again with more Bible questions about other topics. Evidently, he had not repudiated Christianity, so I still keep the communication lines open with him. More recently, I spent three hours answering his Bible questions on the telephone. The man was so willing to hear the truth, and I do not regret speaking to him.
Other Christians with whom I dealt, after sharing numerous verses with them, and after they replied in very negative ways, I broke off contact with them. The verses shared with them were very plain and simple, but they have denominational beliefs that they refused to give up. After I shared the verses with them, they stated the error once more as if I never quoted the verses. They wanted ignorance and I have no reason to force them to believe the verses.
But, again, every situation is different. Some people are so willing to hear the truth. Others are simply too unbearable. Unless absolutely necessary, we do not want to completely cut off contact with religious people. They may come to their senses, they may recover themselves out of the snare of the Devil, and they know to whom they can come for help in spiritual matters. Again, strike a balance—identify the genuine seekers and reach out to them, but stay away from the scoffers unless they reach out to you.
We need to give them the benefit of the doubt. Perhaps they have been in so many groups and read so many so-called “Christian” books that they need more time than others, to get set straight. Maybe they have emotional attachments to certain doctrines or books. Perhaps they have learning disabilities. Then again, maybe they are trying to trip you up, trying to waste your time, trying to “convert” you, or trying to mislead you. Throughout your dealings with them, you need to remember to pray for them, and you need to study your King James Bible so you can be ready for their comments or questions. I cannot stress it enough: you want to be kind, gentle, and as patient with them as possible, but, eventually, with some, you just have to let them go. You will see the above cues, and that is when you just need to find someone else to minister to, to teach, to evangelize, et cetera. You will have to assess the situation and determine what the best course of action is.
Above all, if they do not want to hear from you in regards to the Bible, they can at least see your godly testimony, the Holy Bible living in and through you. You may win them to Jesus Christ by way of your lifestyle. The Apostle Peter talked about believing wives converting their unbelieving husbands by means of the wives’ godly lifestyle. First Peter chapter 3: “ Likewise, ye wives, be in subjection to your own husbands; that, if any obey not the word, they also may without the word be won by the conversation of the wives;  While they behold your chaste conversation coupled with fear.  Whose adorning let it not be that outward adorning of plaiting the hair, and of wearing of gold, or of putting on of apparel;  But let it be the hidden man of the heart, in that which is not corruptible, even the ornament of a meek and quiet spirit, which is in the sight of God of great price.” Your lifestyle may peak their interest and they may come to you for spiritual insight and Bible understanding!
3. HOW TO BEGIN AGAIN WITH THEM.
We just need to be ready when our critics and opponents do want to hear and accept sound Bible answers. “But sanctify the Lord God in your hearts: and be ready always to give an answer to every man that asketh you a reason of the hope that is in you with meekness and fear” (1 Peter 3:15). And what did Paul tell Timothy? We read in 2 Timothy 4:1-2: “ I charge thee therefore before God, and the Lord Jesus Christ, who shall judge the quick and the dead at his appearing and his kingdom;  Preach the word; be instant in season, out of season; reprove, rebuke, exhort with all longsuffering and doctrine.”
We can prepare ourselves by studying and memorizing verses that would address their past doctrinal hang-ups (verses that they once misquoted, verses they used against us, verses they criticized, et cetera). I have learned that this technique has been very helpful in my own ministry. It certainly shocks them when you have those answers the next time around! They see you are not just some “nit-wit” who can quote shallow verses, but rather someone who not only believes the Bible but who actually studies it for himself or herself!
Once you share with them the truth the first time around, they know where to come for answers, so try to be as receptive of them if and when they come around. Some people will come back for answers, and that is fine. Other people will never again discuss the Bible with you, and that is fine, too. Once they hear about the exclusive nature of the Gospel of Grace, that salvation is only found in Jesus Christ (not a church, not in our works, et cetera), they may leave! Once they hear about the King James Bible, they may leave! Once they hear about Paul’s special apostleship, they may leave! Be prepared not to be disappointed. Friend, say the truth anyway and let God take care of the rest!
If they begin again to ask you about spiritual matters, a good starting point for you to say is, “If you want to look at what the Bible says, then I will discuss that topic with you.” This phraseology is useful in weeding out petty/fruitless discussions. I assure you that this approach can be quite a time-saver! When you immediately mention the Bible, it alerts the person that you are not going to “beat around the bush” with your opinions or their opinions, denominations, et cetera. You are showing them that you are serious about Bible doctrine and study, and if they are truly interested in learning God’s truth, they will agree to hear more. Those who want to waste your time will usually not proceed once you say, “If you want to look at what the Bible says….” They do not want to hear verses. Thus, they usually will not bother to continue the conversation. That is when we apply 1 Corinthians 14:38: “But if any man be ignorant, let him be ignorant!”
If they have questions that you cannot answer or of which you are unsure, you can always email me at firstname.lastname@example.org. We have this Bible Q&A website designed just for that purpose: www.forwhatsaiththescriptures.wordpress.com. I would be more than eager to answer them as best as I can using the Scriptures. It is important to keep track of their questions so you can get a better understanding of their mindset.
SOME MORE BRIEF WORDS ABOUT CONDUCTING ONLINE MINISTRY
Sometime back, a brother in the grace ministry recently deactivated his Facebook account. Reading between the lines, and considering what had gone on before, contentious people forced him to leave for an extended period of time. This situation should cause us to stop and think. We need to reassess how we deal with willfully ignorant Christians. The dear brother, evidently, had not considered the counsel we just offered here. We need to adopt and enforce strict measures concerning people who want to waste our time, elevate our blood pressure, and parade their Bible ignorance with their never-ending “vain jangling.” They act very childishly, for they have no accountability hiding behind screen-names. They certainly would not act like that in person. Long before they drive us away, we need to send them packing! They, not we, should go! What do I mean?
In the eight years I have been on Facebook, I have learned to become quite familiar with the “unfriending,” “delete,” and “block” buttons. We grace Christian leaders on Facebook need to be especially mindful that these three buttons are to be used only as last resort, but they are to be used nevertheless. “If any man be ignorant, let him be ignorant” (1 Corinthians 14:38). This is talking about Christians especially!! If they persist in “vain jangling,” I have my three buttons one click away. I have used all three buttons many times before, and I have lowered my blood pressure and removed any “flesh-parade” traps others may have otherwise fallen into.
There is nothing wrong with Bible discussions, but as we know, they are unfruitful and foolishness when verses fall into the wrong hands. I have determined that these people are not going to drive me away. After two attempts to straighten them out, and they deliberately continue in the error, I let them go on their way (Titus 3:9-10). I will not deactivate or delete my accounts on any website. We need a strong grace presence on social media now more than ever. Paul went to the cities, so let us reach the clusters of people online.
You may do as you like, saints, but remember that deactivation or termination of online accounts removes all your posts/articles/tweets from view. I will not deactivate or terminate because I would remove thousands of my posts. At some point, please consider those three buttons rather than deactivation or termination. Warn people in love that if they do not start behaving properly, you are ready to remove them from your online presence. We are not doormats. Been there, done that, and never been more joyful! 🙂
SOME EXTRA TIPS
When witnessing, sometimes you need cycles of patience and distance. Patience and distance will require varying lengths of time. As you witness more and more, and as you mature spiritually, further experience will equip you to better discern a witnessing situation each time. This experience will be very useful because, as we all know, it can be very difficult sometimes to decide whether more patience is needed, or if more distance is needed in a witnessing situation (it is not always clear). Every witnessing situation is totally different from every other, even if it involves the same person and the same topic. Hence, personal experience is one of the best ways to answer the question at hand.
Saint, as you mature in the Word of God, you will be able to better assess the witnessing situation. You will recognize a pattern associated with each person. If you have tried to make the Word of God as plain as possible, and they are still asking the same fundamental questions, or even the same foolish questions, there is a problem… not with you but with them. Those who are persistently stuck on the same Bible topics need to be gently warned that they need to move on. There is more to the Bible than their repetitive questions. They need not waste time on profitless matters. You need not waste time on profitless matters. If they continue in that manner after being warned, that is a clear indication that they are set in their ways. So, you need to move on to someone who is open to reasoning from the Scriptures.
If you have sent various Gospel tracts or booklets to unsaved family members or friends, or if you have sent to denominational relatives or friends numerous booklets or books about dispensational Bible study, and you do not hear from them about that literature, then you have done everything your Lord Jesus Christ has expected. After repeated attempts, it is time to stay silent. You have no further obligation unless those people follow up. It is very tempting to get hung up over one person’s refusal (either for salvation or for Christian edification). I know the frustration, brethren, but do not despair. Unless they request a reply from you, no response is necessary. In fact, unwarranted further involvement might make people more opposed. Again, just move on to those who do want to listen to God’s Word (they are the people we really need to reach; Acts 13:45-52; Acts 18:5-6), and be ready to share it with anyone… even with those who once argued with you who are now returning to ask you for Bible clarity.
Of course, 2 Timothy 2:24-26 says: “ And the servant of the Lord must not strive; but be gentle unto all men, apt to teach, patient,  In meekness instructing those that oppose themselves; if God peradventure will give them repentance to the acknowledging of the truth;  And that they may recover themselves out of the snare of the devil, who are taken captive by him at his will.” We should teach them the Word of God patiently and meekly, but remember 1 Corinthians 14:37-38 says: “ If any man think himself to be a prophet, or spiritual, let him acknowledge that the things that I write unto you are the commandments of the Lord.  But if any man be ignorant, let him be ignorant.” Some people just will not get it because they do not want to get it! That is when you need to break off from the conversation.
The Bible is quite clear that if a Christian refuses to acknowledge Paul’s apostleship, the loving action to take is to let them stay in ignorance. Yes, we value free will as much as our Lord Jesus Christ does! Under the guidance of the Holy Spirit, Paul wrote that we are to expect Christians to be ignorant of his apostleship to us, and there are Christians who do not want to acknowledge his special apostleship either. Those who are saved and who oppose sound Bible study are definitely “opposing themselves,” and unfortunately they are not concerned. We have repeatedly attempted to alert them of their doctrinal error, but they consistently refuse reproof and correction. Dear brethren, its high time to apply 1 Corinthians 14:38. Let them have what they want—spiritual ignorance. They are not just people who do not know better; they have had many opportunities to know the truth, but seminary for many has become Bible cemetery, and that is what they desire. You will save yourself much frustration by not discussing Bible doctrine with those sorts of people unless they ask. Let them come to you.
The good news is that people know who to come to with any Bible questions, so just be on “standby.” God the Holy Spirit will use the Bible verses you did share with them, and He will bring them to their memory. It has been my experience and other Christians, to wait until the opposition has questions, and then they will approach us. For years, these Bible-rejecters may not want to discuss anything further about the Scriptures. Then, one day, here they come with questions, either about salvation or for Bible understanding. That is the result of God’s Word working in them, the verses we shared with them!
Remember the admonition in Ephesians 5:15-17: “ See then that ye walk circumspectly, not as fools, but as wise,  Redeeming the time, because the days are evil.  Wherefore be ye not unwise, but understanding what the will of the Lord is.” Satan has stolen the time that should have been used for the glory of the Lord Jesus Christ. We need to “redeem the time.” We need to buy it back by glorifying the Lord Jesus Christ. We need to share Christ’s finished crosswork with lost people, and we need to teach Christians His Word rightly divided. It is the Devil’s goal to distract us by using bullheaded people who want nothing more than to waste our time. Satan will use Bible critics and Bible scoffers to cause us to waste our time arguing with them, when we could be using our time more wisely. We would be foolish to continue trying to convince those who have no interest in getting set straight. Our time could be better spent on people who do want to hear the truth, than trying to twist arms of people who have thoroughly demonstrated that they do not want to hear it. They want to stay blind and in love we let them pursue what they want.
Whenever you witness to someone, remember this verse (one of my favorite verses): “So shall my word be that goeth forth out of my mouth: it shall not return unto me void, but it shall accomplish that which I please, and it shall prosper in the thing whereto I sent it” (Isaiah 55:11). Also see Colossians 1:5-6: “For the hope which is laid up for you in heaven, whereof ye heard before in the word of the truth of the gospel; Which is come unto you, as it is in all the world; and bringeth forth fruit, as it doth also in you, since the day ye heard of it, and knew the grace of God in truth:” Friend, you are not speaking men’s ideas. God’s Word will always accomplish His will. Let us be faithful in teaching and preaching it, to lost and saved alike. For we read in 1 Corinthians 15:58: “Therefore, my beloved brethren, be ye stedfast, unmoveable, always abounding in the work of the Lord, forasmuch as ye know that your labour is not in vain in the Lord.”
This article, although abbreviated, at least provides some insight to your question. There is no short answer as to the time that should be spent witnessing to one person. It is my hope and prayer that you will use this information to assess each and every witnessing situation in which you find yourself. I wish you the best, brother or sister!