Genesis 4:2-5

Genesis 4:2-5

[2] And she again  bare  his brother  Abel.  was a keeper  of sheep,  but Cain  was a tiller  of the ground.  [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] 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:  [5] But unto Cain  and to his offering  he had not respect.  And Cain  was very  wroth,  and his countenance  fell. 

What is the context of Genesis 4:2-5?