Genesis 3:21

Coats of skins. Before expelling Adam and Eve from the garden, God provided them with more durable clothing, suitable for the hard labor that lay ahead and as protection against the extremes of heat and cold that followed the Fall (PP 61). Also the skins were a constant reminder of their lost innocence, of death as the wages of sin, and of the promised Lamb of God, who would by His own vicarious death take away the sins of the world. He who had been commissioned protector of the animal creation now unhappily found himself taking the life of one of them. They must die that he might live.

The sacrificial service, though not specifically mentioned here, was instituted at this time (PP 68; cf. DA 28). The story of Cain’s and Abel’s sacrifices related in the next chapter shows that the first sons of Adam and Eve were well acquainted with this ritual.

If God had not issued definite regulations concerning sacrifices, His approval of Abel’s offering and His disapproval of Cain’s would have been arbitrary. That Cain did not accuse God of partiality is evidence that he as well as his brother knew what was required. The universality of animal sacrifices in ancient times points to a common origin of this practice.