Cain's offering is not accepted by the Lord and the Lord calls him into question as to why he is angry The Lord gives him an opportunity to change his attitude but instead when he leaves from the presence of God he is still angry.

Ultimately Cain rises up against his brother Abel and kills him for no reason other then the fact that Cain himself according to the bible is evil and so were his deeds.

title: The First Murder
scripture: Genesis 4:1-16