“Fools make a mock at sin: but among the righteous there is favour” (Proverbs 14:9).
The Hebrew wording in this verse is somewhat difficult. The word translated “sin” often refers to a sin-offering. In Leviticus 5:6 it is the trespass offering someone brings, while in the next verse it is the trespass a person has committed. The translators used the context to determine the translation, but in this verse, either translation would have fit well.
Some commentators see this verse as saying that fools mock offering for sin, while others see it as saying that fools mock sin itself. From a practical perspective, it is the same thing.
If someone treats sin as a joke, they are also treating the death of Christ on the cross for that sin as a joke. If sin is no big deal, if it is just something to be treated as funny or entertainment, then they are really mocking the sacrifice that was made on our behalf to pay the penalty for our sin. If you mock the sacrifice of Christ, you are also mocking the sin itself. The exact Hebrew may be difficult, but it makes no difference to the real message of our proverb. Neither sin nor its sacrifice are to be mocked.
God made us with a sense of humour, but we need to use it rightly. When we join in with others in mocking sin, we mock our Saviour. “Among the righteous there is favour.” The contrast is clear — mocking sin and the Saviour is foolish and not righteous behaviour, and when friends, neighbours, or entertainers do this, we need to opt out.