Genesis 4:3-7

3 In the course of time Kayin brought an offering to ADONAI from the produce of the soil;
4 and Hevel too brought from the firstborn of his sheep, including their fat. ADONAI accepted Hevel and his offering
5 but did not accept Kayin and his offering. Kayin was very angry, and his face fell.
6 ADONAI said to Kayin, "Why are you angry? Why so downcast?
7 If you are doing what is good, shouldn't you hold your head high? And if you don't do what is good, sin is crouching at the door - it wants you, but you can rule over it."