There is a time when we should keep our mouths shut. We can be sure that when we are tempted to say something negative or hateful about a neighbor, it is one of those times. It is far better to be gracious towards your neighbor and say something later when you see things clearly, then to comment and regret it for a long time to come. Also . . . Scripture teaches us that if we are going to say something negative - we should first be willing to say it to our neighbor . . . face to face.
The word "despise" here means to hold someone in contempt. It indicates that a man is despising another - disrespecting them and speaking out of that contempt. We are warned several times in Proverbs to hold our tongues when we are feeling contempt for another person. We are reminded that the fool is the one who speaks out of contempt for others. Therefore the wise man knows how to hold his tongue and be gracious - even toward those for whom we feel contempt. We are told that when we despise our neighbor, we lack sense. The word for 'sense' in this passage is literally, "to have heart." We lack God's heart for others when we respond and think of them only in contemptuous ways.
That is something we should consider for a few moments today. How does God respond to those for whom He feels contempt. First of all, we need to remember that the good Samaritan teaches us that our neighbor is not just someone we like. The neighbor in that parable was the Jewish man who was helped by the despised Samaritan. The man set aside racial and social tensions and feelings, and chose to love the man who was in need. In the context of our current proverb, the neighbor is pretty much everyone - even those for whom we would naturally have contempt. To despise them lacks having the heart of God for them. God loves even sinful men. He demonstrated His love for us in that while we were yet sinners, Christ died for us. So, despising our neighbor is foolish - even if we are despising someone we feel is deserving of it. Just remember, we deserved God's judgment and wrath - yet He choose to show mercy while working for our redemption in Christ. Let that be a hindrance to us reacting in our own self-righteous anger and attitude - and an encouragement to react in mercy as our loving Father in heaven does toward us.
The concluding statement of this proverb is that a man of understanding keeps silent. The understanding here may be that he looks at things from the view of God's mercy. It also may be that he sees that a brother offended is harder to win than a walled city. It may be that he sees an opportunity for redemption and reconciliation of far greater worth than one used for a vitriolic diatribe at someone he despises in his emotions. And to be honest - he may just see that the drama that will ensue is far better avoided. His time, he wisely thinks, would be better spent praying for this person and keeping the lines of communication open. In the end, his silence is far wiser than another's words of contempt and disrespect.