Thomas Aquinas

Above, the Apostle proved by experience the power of faith and the insufficiency of the law; but here he proves the same thing through authorities and reasons. And first he proves the power of faith in justifying; second, in this he shows the defect of the law, at the place "For as many as are of the works of the law," etc. The first, however, he proves using a certain syllogism. Hence concerning this he does three things. First he shows the minor premise; second, the major, at the place "But Scripture, foreseeing," etc.; third, he infers the conclusion, at the place "Therefore they who are of faith," etc. Concerning the first he does two things. First he proposes a certain authority, from which he elicits the minor; second, he concludes it, at the place "Know ye therefore," etc.

He says therefore: truly justice and the Holy Spirit are from faith, as it is written, Genesis 15:6, and it is quoted in Romans 4:3, that "Abraham believed God," etc. Where it must be noted that justice consists in the rendering of what is due; but man owes something to God, and something to himself, and something to his neighbor. But that he owes something to himself and to his neighbor, this is on account of God. Therefore the highest justice is to render to God what is His. For if you render to yourself or to your neighbor what you owe, and you do not do this on account of God, you are more perverse than just, since you place your end in man. But whatever is in man is God's — both the intellect and the will and the body itself — yet nonetheless in a certain order, because lower things are ordered to higher things, and exterior things to interior things, namely to the good of the soul; but the highest thing in man is the mind. And therefore the first thing in the justice of man is that the mind of man be subjected to God, and this comes about through faith. 2 Corinthians 10:3: "bringing into captivity every understanding unto the obedience of Christ." Thus therefore it must be said in all things, that God is the first principle in justice, and he who gives to God — namely, the highest thing that is in himself — by subjecting the mind to Him, is perfectly just. Romans 8:14: "they who are led by the Spirit of God, they are the sons of God." And therefore he says "Abraham believed God," that is, he subjected his mind to God through faith. Ecclesiasticus 2:6: "Believe God, and he will recover thee," etc., and below, "ye that fear the Lord, believe him," etc. And "it was reputed to him unto justice," that is, the very act of believing, and faith itself, was for him — and is for all others — a sufficient cause of justice; and that it is reputed to him unto justice is, outwardly, from men, but inwardly it is given by God, who justifies those who have faith, through charity working, by remitting their sins to them.

From this authority, however, he concludes the minor proposition, saying "Know ye therefore," etc., as if to say: from this someone is called the son of another, that he imitates his works; if therefore you are sons of Abraham, do the works of Abraham, John 8:39. But Abraham did not seek to be justified through circumcision, but through faith; therefore also those who seek to be justified through faith are sons of Abraham. And this is what he says: because Abraham is just from faith, by this — that he believed God, and it was reputed to him unto justice — therefore know ye, that they who are of faith, that is, who believe by faith that they are justified and saved, these are sons of Abraham, namely by imitation and instruction. Romans 9:8: "they who are the sons of the promise are accounted in the seed," etc. Luke 19:9, it is said to Zacchaeus: "This day salvation from God has come to this house, because he also is a son of Abraham," etc. And Matthew 3:9: "God is able of these stones" — that is, of the gentiles — "to raise up sons of Abraham," inasmuch, namely, as he makes them believers.

Consequently, when he says "But Scripture, foreseeing," etc., he sets out the major premise, which is namely, that it was foretold to Abraham that in his seed all nations would be blessed. And this is what he says, "But Scripture, foreseeing," introducing God speaking to Abraham, says — Genesis 12:3 — that God foretold to Abraham that "in thee," that is, in those who, in likeness to you, will be your sons through the imitation of faith, "all nations shall be blessed." Matthew 8:11: "Many shall come from the east and the west," etc.

Consequently, when he says "Therefore they who are of faith," etc., he infers the conclusion from the premises. Hence the argument can be formed thus: God the Father announced to Abraham that in his seed all nations would be blessed; but those who seek to be justified through faith are sons of Abraham; therefore they who are of faith, that is, who seek to be justified through faith, shall be blessed with the faithful — that is, believing — Abraham.