Genesis 4:5-8

5but He had no regard for Cain and his offering. So Cain became very angry, and his countenance fell.

6“Why are you angry,” said the LORD to Cain, “and why has your countenance fallen? 7If you do what is right, will you not be accepted? But if you refuse to do what is right, sin is crouching at your door; it desires you,1 but you must master it.”

8Then Cain said to his brother Abel, “Let us go out to the field.”2 And while they were in the field, Cain rose up against his brother Abel and killed him.