Genesis 4:3-5, 15, 25

In the course of time Cain brought some of the fruits of the soil as an offering to the LORD. And Abel also brought an offering—fat portions from some of the firstborn of his flock. The LORD looked with favor on Abel and his offering, but on Cain and his offering he did not look with favor. So Cain was very angry, and his face was downcast.

But the LORD said to him, “Not so; anyone who kills Cain will suffer vengeance seven times over.” Then the LORD put a mark on Cain so that no one who found him would kill him.

Adam made love to his wife again, and she gave birth to a son and named him Seth, saying, “God has granted me another child in place of Abel, since Cain killed him.”