Genesis

4:1 And Adam knew Eve his wife; and she conceived, and bare Cain, and said, I have gotten a man from the LORD.
4:2 And she again bare his brother Abel. And Abel was a keeper of sheep, but Cain was a tiller of the ground.
4:3 And in process of time it came to pass, that Cain brought of the fruit of the ground an offering unto the LORD.
4:4 And Abel, he also brought of the firstlings of his flock and of the fat thereof. And the LORD had respect unto Abel and to his offering:
4:5 But unto Cain and to his offering he had not respect. And Cain was very wroth, and his countenance fell.
4:6 And the LORD said unto Cain, Why art thou wroth? and why is thy countenance fallen?
4:7 If thou doest well, shalt thou not be accepted? and if thou doest not well, sin lieth at the door. And unto thee [shall be] his desire, and thou shalt rule over him.
4:8 And Cain talked with Abel his brother: and it came to pass, when they were in the field, that Cain rose up against Abel his brother, and slew him.