"Revenge sounds sweet" - when someone hurts you. We want to see people pay for their wrongs. That's human nature anyway. God has a different idea about revenge. See what the bible says about it below.
You shall not take vengeance, nor bear any grudge against the children of your people, but you shall love your neighbor as yourself: I am the LORD. Leviticus 19:18 (NKJV)
Do not say, "I will recompense evil"; Wait for the LORD, and He will save you. Proverbs 20:22 (NKJV)
Whoever digs a pit will fall into it, And he who rolls a stone will have it roll back on him. Proverbs 26:27 (NKJV)
Repay no one evil for evil. Have regard for good things in the sight of all men. If it is possible, as much as depends on you, live peaceably with all men. Beloved, do not avenge yourselves, but rather give place to wrath; for it is written, "Vengeance is Mine, I will repay," says the Lord. Romans 12:17-19 (NKJV)
"You have heard that it was said, 'An eye for an eye and a tooth for a tooth.' "But I tell you not to resist an evil person. But whoever slaps you on your right cheek, turn the other to him also. "If anyone wants to sue you and take away your tunic, let him have your cloak also. "And whoever compels you to go one mile, go with him two. "Give to him who asks you, and from him who wants to borrow from you do not turn away. "You have heard that it was said, 'You shall love your neighbor and hate your enemy.' "But I say to you, love your enemies, bless those who curse you, do good to those who hate you, and pray for those who spitefully use you and persecute you, "that you may be sons of your Father in heaven; for He makes His sun rise on the evil and on the good, and sends rain on the just and on the unjust. Matthew 5:38-45 (NKJV)
which is manifest evidence of the righteous judgment of God, that you may be counted worthy of the kingdom of God, for which you also suffer; since it is a righteous thing with God to repay with tribulation those who trouble you, and to give you who are troubled rest with us when the Lord Jesus is revealed from heaven with His mighty angels, in flaming fire taking vengeance on those who do not know God, and on those who do not obey the gospel of our Lord Jesus Christ. 2 Thessalonians 1:5-8 (NKJV)