Genesis 4:5-9

but for Cain and his offering He had no regard. So Cain became very angry and his face was gloomy.

Then the Lord said to Cain, “Why are you angry? And why is your face gloomy?

If you do well, will your face not be cheerful? And if you do not do well, sin is lurking at the door; and its desire is for you, but you must master it.”

Cain talked to his brother Abel; and it happened that when they were in the field Cain rose up against his brother Abel and killed him.

Then the Lord said to Cain, “Where is Abel your brother?” And he said, “I do not know. Am I my brother’s keeper?”