Redemption is styled by the "Catechism of the Council of Trent" (1, v, 15) "complete, integral in all points, perfect and truly admirable". Such is the teaching of St. Paul: "where sin abounded, grace did more abound" (Rom., v, 20), that is, evil as the effects of sin are, they are more than compensated by the fruits of Redemption."
Redemption
Part I
The restoration of man from the bondage of sin to the liberty of the children of God through the satisfactions and merits of Christ.
The word redemptio is the Latin Vulgate rendering of Hebrew kopher and Greek lytron which, in the Old Testament means generally a ransom-price. In the New Testament, it is the classic term designating the "great price" (I Cor., vi, 20) which the Redeemer paid for our liberation. Redemption presupposes the original elevation of man to a supernatural state and his downfall from it through sin; and inasmuch as sin calls down the wrath of God and produces man's servitude under evil and Satan, Redemption has reference to both God and man. On God's part, it is the acceptation of satisfactory amends whereby the Divine honour is repaired and the Divine wrath appeased. On man's part, it is both a deliverance from the slavery of sin and a restoration to the former Divine adoption, and this includes the whole process of supernatural life from the first reconciliation to the final salvation. That double result, namely God's satisfaction and man's restoration, is brought about by Christ's vicarious office working through satisfactory and meritorious actions performed in our behalf.
I. NEED OF REDEMPTION
When Christ came, there were throughout the world a deep consciousness of moral depravation and a vague longing for a restorer, pointing to a universally felt need of rehabilitation (see Le Camus, "Life of Christ", I, i). From that subjective sense of need we should not, however, hastily conclude to the objective necessity of Redemption. If, as is commonly held against the Traditionalist School, the low moral condition of mankind under paganism or even under the Jewish Law is, in itself, apart from revelation no proof positive of the existence of original sin, still less could it necessitate Redemption. Working on the data of Revelation concerning both original sin and Redemption, some Greek Fathers, like St. Athanasius (De incarnatione, in P. G., XXV, 105), St. Cyril of Alexandria (Contra Julianum in P. G., LXXV, 925) and St. John Damascene (De fide orthodoxa, in P. G, XCIV, 983), so emphasized the fitness of Redemption as a remedy for original sin as almost to make it appear the sole and necessary means of rehabilitation. Their sayings, though qualified by the oft-repeated statement that Redemption is a voluntary work of mercy, probably induced St. Anselm (Cur Deus homo, I) to pronounce it necessary in the hypothesis of original sin. That view is now commonly rejected, as God was by no means bound to rehabilitate fallen mankind. Even in the event of God decreeing, out of his own free volition, the rehabilitation of man, theologians point out other means besides Redemption, v.g. Divine condonation pure and simple on the sole condition of man's repentance, or, if some measure of satisfaction was required, the mediation of an exalted yet created interagent. In one hypothesis only is Redemption, as described above, deemed absolutely necessary and that is if God should demand an adequate compensation for the sin of mankind. The juridical axiom "honor est in honorante, injuria in injuriato" (honour is measured by the dignity of him who gives it, offence by the dignity of him who receives it) shows that mortal sin bears in a way an infinite malice and that nothing short of a person possessing infinite worth is capable of making full amends for it. True, it has been suggested that such a person might be an angel hypostatically united to God, but, whatever be the merits of this notion in the abstract, St. Paul practically disposes of it with the remark that "both he that sanctifieth, and they who are sanctified, are all of one" (Heb., ii, 11), thus pointing to the God-Man as the real Redeemer.
MODE OF REDEMPTION
The real redeemer is Jesus Christ, who, according to the Nicene creed, "for us men and for our salvation descended from Heaven; and was incarnate by the Holy Ghost of the Virgin Mary and became man. He was also crucified for us, suffered under Pontius Pilate and was buried". The energetic words of the Greek text [Denzinger-Bannwart, n. 86 (47)], enanthropesanta, pathonta, point to incarnation and sacrifice as the groundwork of Redemption. Incarnation — that is, the personal union of the human nature with the Second Person of the Blessed Trinity — is the necessary basis of Redemption because this, in order to be efficacious, must include as attributions of the one Redeemer both the humiliation of man, without which there would be no satisfaction, and the dignity of God, without which the satisfaction would not be adequate. "For an adequate satisfaction", says St. Thomas, "it is necessary that the act of him who satisfies should possess an infinite value and proceed from one who is both God and Man" (III:1:2 ad 2um). Sacrifice, which always carries with it the idea of suffering and immolation (see Lagrange, "Religions semitiques", 244), is the complement and full expression of Incarnation. Although one single theandric operation, owing to its infinite worth, would have sufficed for Redemption, yet it pleased the Father to demand and the Redeemer to offer His labours, passion, and death (John, x, 17-18). St. Thomas (III:46:6 ad 6um) remarks that Christ wishing to liberate man not only by way of power but also by way of justice, sought both the high degree of power which flows from His Godhead and the maximum of suffering which, according to the human standard, would be considered sufficient satisfaction. It is in this double light of incarnation and sacrifice that we should always view the two concrete factors of Redemption, namely, the satisfaction and the merits of Christ.