"But to those who rebuke the wicked will be delight, and a good blessing will come upon them"
This proverb is a part of a couplet with the proverb before it. In that proverb Solomon is pointing out the consequences that will come to those who praise the wicked or find it convenient to overlook their wickedness. Remember that this kind of action takes place in politics and business a lot. Someone who is wicked is in a position of power or influence and rather than expose their wickedness, you want something from them; so you excuse what they are like or you praise them for a quality that they don't possess in order to butter them up to get what you want out of them. In this proverb, Solomon follows up with this idea, with insight into what happens when you rebuke the wicked instead of trying to excuse or embrace or praise the wicked.
This is the Hebrew word tokeha which means rebuke or reprove. This carries with it the idea of a verbal reprimand and or correction. When a person is wicked and it is the appropriate time, a rebuke, Solomon says, is the thing to do. Too often people know the wickedness that a person is doing and they say nothing.
What is interesting is that Solomon doesn't say that you will win the wicked. Because most of the time you won't, but God will reward you for standing up to the wicked and for reminding yourself that their behavior is not okay. It is the fact that you would seek to point out the destructive actions of the person that God says He will bless.
This word does not appear in the original Hebrew sentence but has been supplied to give a sense that there is a continuation from the previous proverb. The word wicked in the previous proverb is the Hebrew word rasa which means wicked, criminal. This is the last category of sin in the Old Testament mind-set. This is the person who does that which is evil and has no concern about getting back to looking righteous or behaving in a righteous manner. This is the person who lives in sin and will not repent. This is the person who lives beyond the boundaries of the Ten Commandments. They lie and think nothing of it. They steal and say it is okay. They commit adultery and consider it normal. They use physical violence to get what they want. They rebel against authority and disrespect those over them. They have themselves as the object of their affection rather than God. All these and many others represent a life based on selfishness in a permanent way, and this is wickedness in the Old Testament.
This person needs to have honest, law-abiding citizens point out that it is not okay for them to endanger the civil structure of the community by their actions. It is the timid and fearful that allow the wicked to flourish by not saying anything when they use violence; when they commit abominable acts on others; when they steal and lie and scheme of ways to take other people's goods.
This is the Hebrew word noam which means pleasant, delightful, beautiful.
This is the word berakah which means blessing or benefit. The idea is that when wickedness is rebuked, there is a blessing released to the community and the individual. Often it is that there is less destruction caused by the wicked. The wicked are supremely selfish people who do not let anyone's morals stop them from getting what they want; and therefore they bring heartache, destruction, strife, and wounds. Therefore rebuking this kind of activity brings a blessing by pushing back the advance of wicked behavior and brings peace and harmony between people. It is a blessing often by the absence of a negative.