3:15 I will put enmity. God graciously converts the depraved woman’s affections from Satan to Himself.
your offspring and her offspring. Humanity is now divided into two communities: the redeemed, who love God, and the reprobate, who love self (John 8:33, 44; 1 John 3:8). The division finds immediate expression in the hostility of Cain against Abel (ch. 4). This prophecy finds ultimate fulfillment in the triumph of the Second Adam, and the community united with Him, over the forces of sin, death, and the devil (Dan. 7:13, 14; Rom. 5:12–19; 16:20; 1 Cor. 15:45–49; Heb. 2:14, 15).
head . . . heel. The suffering Christ is victorious. He has already won the victory at the Cross by providing an atonement for the saints (Col. 2:13–15) and will consummate it at His Second Coming (2 Thess. 1:5–10).