[1.20.29] And Cain answered: "O brother Abel, if you have come to take petty vengeance on me, your murderer, then do to me according to justice, but spare your blessed sister and her children!"
[1.20.30] Then the voice spoke again, saying: "Cain, he who commits a crime is a sinner, but he who repays evil with evil is a servant of sin. The one who rewards good with good has paid his debt, but there is nothing left for him. He, who rewards a good deed manifold, is worthy of his brothers. However, before God only one thing counts and that is, to return good for evil, bless those who curse their benefactors and give one's life for death.