Thomas Aquinas, on Rom 3:25

“Whom God hath proposed to be a propitiation, through faith in his blood, to the shewing of his justice, for the remission of former sins,”

“Second, he shows whence this redemption has efficacy, when he says whom God has proposed to be a propitiation. For Christ's satisfaction was efficacious for justifying and redeeming by the fact that God had assigned him to this in his plan, which he designates when he says whom God has proposed to be a propitiation: according to the purpose of him who accomplishes all things according to the counsel of his will (Eph 1:11). Or proposed, that is, he put forward for all, because the human race had no way of making satisfaction unless God himself gave them a redeemer and satisfier: he sent redemption to his people (Ps 111:9). And so, while making satisfaction, he redeems us from the debt of sin and obtains pardon for our sins, which the Psalmist begged: be propitious to our sins (Ps 79:9); and this is why he calls him a propitiation: propitiation (1 John 2:2). As a figure of this it was commanded in Exodus that a propitiatory, i.e., Christ, be placed on the ark, i.e., the Church (Exod 25:17). Third, he indicates how the effect of redemption reached us, when he says, through faith in his blood, i.e., faith concerning his blood poured out for us. For in order to satisfy for us, it was fitting that he undergo the penalty of death for us, a penalty man had incurred by sin, as indicated in Genesis, in the day that you eat of it you shall die (Gen 2:17). Hence 1 Peter states, for Christ also died for sins once for all (1 Pet 3:18). This death of Christ is applied to us through faith, by which we believe that the world has been redeemed by his death: I live by faith in the Son of God, who loved me and gave himself for me (Gal 2:20). For even among men payment made by one man does not benefit another, unless he considers it valid. And so it is clear how there is justification through faith in Jesus Christ, as has been stated above. But because he had stated above that God's justice is manifested now, he considers this manifestation. First, he touches on the manner of this manifestation, saying to the showing. As if to say: I say that we are justified by the redemption of Christ and by faith in his blood, to the showing of his justice, i.e., to the end that God might show his justice, and this for the remission of former sins. For in remitting former sins, which the law could not remit or men by their own power sufficiently guard against, God showed that the justice by which they are made just by God is necessary for men. But only through the blood of Christ could sins both present and past be remitted, because the power of Christ's blood works through man's faith, which the men who lived before his passion had, just as we have: since we have the same spirit of faith . . . we too believe (2 Cor 14:13). Hence another way of reading it is: for the remission of the sins of those men who preceded the passion of Christ: he will tread our iniquities under foot and he will cast all our sins into the depth of the sea (Mic 7:19).”

Imported from an open dataset — not yet checked against the printed edition.