Thomas Aquinas, on Heb 8:10

“For this is the testament which I will make to the house of Israel after those days, saith the Lord: I will give my laws into their mind, and in their heart will I write them: and I will be their God, and they shall be my people:”

“403. – Then (v. 10) he describes the qualities of the New Testament. In regard to this he does two things: first, he describes the way it was announced; secondly, its effect (v. 10b). 404. – He says, therefore, This is the covenant that I will make with the house of Israel after those days. Making implies a suitable order; hence, he says, after those days, i.e., after the Law was given. For a new law should have been given after the old; just as a master is given after a pedagogue, in order that man recognize his infirmity. This, therefore, shows the fitness of the time when the New Testament was given. The manner in which it was given is twofold: in one way by externals, by proposing words suited to their understanding. This man can do; and that is the way the Old Testament was given. In another way by acting inwardly, and this is peculiar to God: 'the inspiration of the Almighty gives understanding' (Jb. 32:8). This is the way the New Testament was given, because it consists in the outpouring of the Holy Spirit, Who instructs inwardly. But it is not enough to know, for one must act. Therefore, He first enlightens the intellect to understand; hence, he says, I will put my laws into their minds. He uses the plural, because there are various precepts and counsel. This the Holy Spirit does: 'His unction teaches you' (1 Jn. 2:27); 'He will teach you all things (Jn. 14:26). Furthermore, He inclines the will to act well; hence, it is impressed on their heart. In regard to this he says, and write them on their hearts, i.e., I will write charity on their knowledge: 'Above all things have charity, which is the bond of perfection' (Col. 3:14); 'The charity of God is poured forth in our hearts by the Holy Spirit who is given to us' (Rom. 5:5). This is the epistle of which he says in 2 Cor. (3:3): 'Not in ink, but with the Spirit of the living God; not in tablets of stone, but in the fleshly tablets of the heart.' 405. – Having mentioned the qualities of the New Testament from the way it was given, the Apostle now describes three of its effects: the first is man's perfect union with God; the second is perfect knowledge of God (v. 11); the third is the remission of sins (v. 12). 406. – In regard to the first it should be noted that the help of God's grace is required, if man is to be united with God, because one's own power is not capable of this: 'I have loved you with an everlasting love; therefore, have I drawn you, taking pity on you' (Jer. 31:3): first, therefore, he touches on that union from God's side; secondly, from mans' side (v. 10c). He says, therefore: I will be their God. Now the name 'God' signifies universal providence. Therefore, He is our God, when He has a care for us and draws our hearts to Himself. Therefore, from the fact that he says, I will be their God, the effect follows that they shall be my people, i.e., they will show themselves my people. For, as Augustine says in The City of God: A people is an assembled multitude joined together by the consent of right and common utility. Therefore, when they consent to the rights of the divine law in order to be useful to each other and tend to God, then they are God's people: 'And they shall be his people; and God himself with them shall be their God' (Rev. 21:3).”

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