That has absolutely nothing to do with any laws at all. All "laws" mean in this sense are the books and writings that Moses wrote.
In Matthew 5 38-48, Jesus directly says that the laws of revenge are ones that not longer are applied:
"You have heard that it was said, an eye for an eye and a tooth for a tooth. But I say to you, Do not resist one who is evil. But if any one stirkes you on the right cheek, turn to him the other also; and if any one would sue you and take your coat, let him have your cloak as well;and if any one forces you to go one mile, go with him two miles. Give to him who begs from you, and do not refuse him who would borrow from you. You have heard that it was said, You shall love your neighbor and hate your enemy. But I say to you, Love your enemies and pray for those who persecute you, so that you nay be sons of your Father who is in heaven for he makes the sun rise on the evil and on the good, and sends rain to fall on the just and unjust. For if you love those who love you what reward have you? Do not even the tax collectors do the same? Do not even the Gentiles do the same? You, therefore, must be perfect, as your heavenly Father is perfect."
Chapter Five of Matthew does a great job of telling exactly how laws changed from the OT. Please look there for further reference. ^_^
The only gov't that God instucted was changed by God Himself. And the laws were changed to love those who have done harm to you and your family and to forgive them. This Amish do a good job of displaying this. They have no hard feelings for the man who murdered those children last week, but instead forgive and move on right away. And even more, they pray for his family.