Genesis 4:1-8

And Adam knew Eve his wife: who conceived and brought forth Cain, saying: I have gotten a man through God. And again she brought forth his brother Abel. And Abel was a shepherd, and Cain a husbandman. And it came to pass after many days, that Cain offered, of the fruits of the earth, gifts to the Lord. Abel also offered of the firstlings of his flock, and of their fat: and the Lord had respect to Abel, and to his offerings. But to Cain and his offerings he had no respect: and Cain was exceedingly angry, and his countenance fell. And the Lord said to him: Why art thou angry? And why is thy countenance fallen? If thou do well, shalt thou not receive? But if ill, shall not sin forthwith be present at the door? But the lust thereof shall be under thee, and thou shalt have dominion over it. And Cain said to Abel his brother: Let us go forth abroad. And when they were in the field, Cain rose up against his brother Abel, and slew him.