Proverbs 9:7 (NKJV) — 7 “He who corrects a scoffer gets shame for himself, And he who rebukes a wicked man only harms himself.
When there is no point in reproof or rebuke. It does no good to correct a scoffer or to rebuke a deliberately wicked person. Prudence, caution, and tact are needed in dealing with this kind of person. Such a scoffer or wicked person, when corrected or rebuked, will often resort to finding supposed inconsistencies and sins in the person who is correcting and rebuking him. Jesus addressed this situation in Matthew 7:6.
Matthew 7:6 (NKJV) — 6 “Do not give what is holy to the dogs; nor cast your pearls before swine, lest they trample them under their feet, and turn and tear you in pieces.