The details of the offerings at Gen 4:3-4, and other details from the chapter, greatly resemble what is required under the Mosaic law. What are we to make of this?

Without giving a long list, it is worth observing that sacrifices were meant to be offered with faith and contrition; that “the fat” of the sacrifice was offered; that “first fruits” were offered; that Israelites were required by law to care for their brothers; that murder was severely punished; that blood revenge was prevented through the practices of sanctuary cities; etc. All these details seem to point up the fact that God used earlier events in Genesis as a kind of template on which the Mosaic law was based. It certainly seems as if the details would be viewed that way by students of the Mosaic law glancing back at Genesis. It is also possible that the author of Genesis, also having authored Deuteronomy, would expect the business about the city Cain escaped to (at Gen 4:17) to be read alongside the “sanctuary city” rules of Deut 19. Indeed, even the very word, or קוּם or qum, translated “rose up,” can also be found at Deut 19:11: “But if any man hate his neighbour, and lie in wait for him, and rise up against him, and smite him mortally that he die… .” One must, of course, bear in mind that the author of Genesis was aware of God’s law, even it had not be handed down yet in the narrative. This does not, of course, mean that the antediluvian patriarchs were aware of or lived under the law—certainly not in detail.