of all creatures, but every man; not in the sense, however, of such as existed apart from the family of Adam, but such as were aware of his crime, and knew him to be a murderer. For Cain is evidently afraid of revenge on the part of relatives of the slain, that is to say, of descendants of Adam, who were either already in existence, or yet to be born. Though Adam might not at this time have had “many grandsons and great-grandson,” yet according to Gen 4:17 and Gen 5:4, he had undoubtedly other children, who might increase in number, and sooner or later might avenge Abel's death. For, that blood shed demands blood in return, “is a principle of equity written in the heart of every man; and that Cain should see that earth full of avengers is just like a murderer, who sees avenging spirits (Ἐρινύες) ready to torture him on every hand.”
Verse 15
Although Cain expressed not penitence, but fear of punishment, God displayed His long-suffering and gave him the promise, “ Therefore (לכן not in the sense of כן לא, but because it was the case, and there was reason for his complaint) whosoever slayeth Cain, vengeance shall be taken on him sevenfold.” קין כּל־הרג, is cas. absolut. as in Gen 9:6; and הקּם avenged, i.e., resented, punished, as Exo 21:20-21. The mark which God put upon Cain is not to be regarded as a mark upon his body, as the Rabbins and others supposed, but as a certain sign which protected him from vengeance, though of what kind it is impossible to determine. God granted him continuance of life, not because banishment from the place of God's presence was the greatest possible punishment, or because the preservation of the human race required at that time that the lives of individuals should be spared, - for God afterwards destroyed the whole human race, with the exception of one family, - but partly because the tares were to grow with the wheat, and sin develop itself to its utmost extent, partly also because from the very first God determined to take punishment into His own hands, and protect human life from the passion and wilfulness of human vengeance.
verses 16-24
The family of the Cainites. - Gen 4:16. The geographical situation of the land of Nod, in the front of Eden (קדמת, see Gen 2:14), where Cain settled after his departure from the place or the land of the revealed presence of God (cf. Jon 1:3), cannot be determined. The name Nod denotes a land of flight and banishment, in contrast with Eden, the land
