Eclectic theologian that he was, it is not surprising that Milton's theory of the Redemption has its sources in Augustine, Anselm, Calvin, and many other theologians and preachers of lesser note. The Bible remained his prime source, though it seems his interpretation of the Redemption as drawn from the Scriptures was always colored by his theological reading. It will be the purpose of this essay to indicate the particular nuance of the "satisfaction" theory of the Redemption that Milton used in Book III of Paradise Lost and to indicate further his sources, some of which are known, some of which can only be conjectured.