Jesus gave good advice concerning trying to speak of spiritual things with those who hold them in disdain:
Mat 7:6 Give not that which is holy unto the dogs, neither cast ye your pearls before swine, lest they trample them under their feet, and turn again and rend you.
What was he saying here.
In Jesus time, dogs were regarded as unclean animals, most were savage in nature. We can get a picture of them snarling, brutish, recoiling or attacking those who approached them. The swine were similar in nature, who also enjoyed wallowing in the filth of their surroundings. This describes many people today and their reactions to witnessing, preaching, or teaching of the Word of God.
Proclaiming the gospel is a mandate for all who follow Christ, whether a layman or preacher. But, the Lord gives us guidelines for when to stop, and let the person live by their decisions. This verse helps us to know when to say nothing more.
When you see your witness is held in contempt, that the priceless gift you are offering is being rejected; it's time to stop; but turn to prayer. Prayer changes things.
The value of the truth your offering is repulsive to them, it can't be forced on anyone.
When I come into a situation like this, I pray that God will work in the lives of these hardened hearts, and that God would put someone else in their path, that may be able to turn them to Christ. None of us can be all things to all people; but the Lord has infinite ways to bring about change for that hardened one who seems unreachable. There is no bottom to the Lord's ways of bringing change into the most difficult situations. His goal is to win that soul to Christ; that not one soul is lost.
Consider how Jesus dealt with his adversaries. He loved even them, but it was tough love. He told them what they were, and where they were headed if they didn't change. He didn't put it in sweet and savory language either. Read his encounters with the Pharisee's and Saducees in the gospels, especially Matthew ch. 23 for an example.
B.W. Johnson gives a good description for us.
Give not that which is holy unto dogs. The dog was regarded an unclean animal by the Jewish law. They probably represent snarling, scoffing opposers. The characteristic of dogs is brutality. To try to instill holy things into such low, unclean, and sordid brutal minds is useless.
Neither cast pearls before swine. The swine were also unclean. They would have no use for pearls, and perhaps would rush upon those who scattered the pearls. So, too, there are men so dull, imbruted and senseless, as to reject the pearls of truth. It is our duty to help and to try to save others, but we must use common sense.
And from the JFB commentary:
Prostitution of Holy Things. The opposite extreme to that of censoriousness is here condemned - want of discrimination of character.
Give not that which is holy unto the dogs — savage or snarling haters of truth and righteousness.
neither cast ye your pearls before swine — the impure or coarse, who are incapable of appreciating the priceless jewels of Christianity. In the East, dogs are wilder and more gregarious, and, feeding on carrion and garbage, are coarser and fiercer than the same animals in the West. Dogs and swine, besides being ceremonially unclean, were peculiarly repulsive to the Jews, and indeed to the ancients generally.
lest they trample them under their feet — as swine do.
and turn again and rend you — as dogs do. Religion is brought into contempt, and its professors insulted, when it is forced upon those who cannot value it and will not have it. But while the indiscriminately zealous have need of this caution, let us be on our guard against too readily setting our neighbors down as dogs and swine, and excusing ourselves from endeavoring to do them good on this poor plea.
Some good cross reference verses that go with this:
Mat 10:14 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.
Mat 10:15 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.
Shake off the dust of your feet. This was done when there was a positive rejection of the gospel. It was a symbolical act, signifying that all responsibility for the stubborn household or city had ended. Compare Mar_6:11 and Act_13:51. Nor can the gospel be forced upon an unwilling people in any age. B.W. Johnson comm.
Mar 6:11 And whosoever shall not receive you, nor hear you, when ye depart thence, shake off the dust under your feet for a testimony against them. Verily I say unto you, It shall be more tolerable for Sodom and Gomorrha in the day of judgment, than for that city.
Act 13:45 But when the Jews saw the multitudes, they were filled with envy, and spake against those things which were spoken by Paul, contradicting and blaspheming.
Act 13:46 Then Paul and Barnabas waxed bold, and said, It was necessary that the word of God should first have been spoken to you: but seeing ye put it from you, and judge yourselves unworthy of everlasting life, lo, we turn to the Gentiles.
Act 13:47 For so hath the Lord commanded us, saying, I have set thee to be a light of the Gentiles, that thou shouldest be for salvation unto the ends of the earth.
It was necessary. The preachers met this attitude of the Jews by boldly stating their purpose to turn from them to the Gentiles. It was God's will that the Gospel should first be offered to the chosen people. See Act_1:8; Act_3:26; Rom_1:16. While the chosen people were to have the first opportunity, yet "God had put no difference" between Jew and Greek. As soon as the Jewish audiences manifested a self-willed, contradictory spirit, instead of engaging in idle disputation, the apostles were wont to turn to the Gentiles. B.W. Johnson comm.
Php 3:2 Beware of dogs, beware of evil workers, beware of the concision.
evil workers — (2Co_11:13), “deceitful workers.” Not simply “evildoers” are meant, but men who “worked,” indeed, ostensibly for the Gospel, but worked for evil: “serving not our Lord, but their own belly” (Php_3:19; compare Rom_16:18). Translate, “The evil workmen,” that is, bad teachers (compare 2Ti_2:15).
There is a time and a place for giving witness for the Lord. I've been blessed a number of times to bring someone to a place of praying with them for salvation, seeing their faces when they became born again was a moment of pure joy; another soul transferred from the kingdom of darkness, into the kingdom of God. But, I've also been in situations that I knew my witness for the Lord was held in contempt, and saying nothing was the best thing to do. Discernment and common sense is necessary for each situation.