Genesis 4:1-5

Adam had sexual relations with his wife Eve, and she became pregnant and gave birth to Cain. Eve said, “With the LORD’s help, I have given birth to a man.” After that, Eve gave birth to Cain’s brother Abel. Abel took care of flocks, and Cain became a farmer. Later, Cain brought some food from the ground as a gift to God. Abel brought the best parts from some of the firstborn of his flock. The LORD accepted Abel and his gift, but he did not accept Cain and his gift. So Cain became very angry and felt rejected.