Thomas Aquinas Commentary Hebrews 8:10-13

"For this is the covenant that I will make with the house of Israel After those days, saith the Lord; I will put my laws into their mind, And on their heart also will I write them: And I will be to them a God, And they shall be to me a people: And they shall not teach every man his fellow-citizen, And every man his brother, saying, Know the Lord: For all shall know me, From the least to the greatest of them. For I will be merciful to their iniquities, And their sins will I remember no more. In that he saith, A new [covenant] he hath made the first old. But that which is becoming old and waxeth aged is nigh unto vanishing away." — Hebrews 8:10-13 (ASV)

Having mentioned the qualities of the New Testament based on how it was given, the Apostle now describes three of its effects. The first is a person’s perfect union with God; the second is perfect knowledge of God (v. 11); and the third is the remission of sins (v. 12).

Regarding the first effect, it should be noted that the help of God’s grace is required if a person 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 (Jeremiah 31:3). First, therefore, the Apostle touches on this union from God’s side, and second, from the human side (v. 10c).

He says, therefore, I will be their God. The name “God” signifies universal providence. Therefore, He is our God when He cares for us and draws our hearts to Himself. From His statement, I will be their God, the effect follows that they shall be my people—that is, they will show themselves to be His people. For, as Augustine says in The City of God, a people is an assembled multitude joined together by common consent to law and a shared purpose. Therefore, when they consent to the laws of the divine law in order to be useful to each other and draw near to God, then they are God’s people: And they shall be his people; and God himself with them shall be their God (Revelation 21:3).

Next, when the Apostle says, And they shall not teach every one his fellow, he presents the second effect of the New Testament. In this regard, he does two things: first, he gives the sign of that effect, and second, the effect itself (v. 11b).

The sign of perfect knowledge is that a person does not need to be taught, because teaching is the path to acquiring knowledge; therefore, teaching ceases when knowledge has been perfectly acquired. But does one person not teach another in the New Testament? Taken literally, it seems not. Yet the Apostle calls himself the teacher of the Gentiles: Some pastors and teachers (Ephesians 4:11); He that teaches, in doctrine (Romans 12:7).

I answer that what is stated here can be understood in two ways. In one way, it refers to the present state. In this case, it is not true for everyone, but only for the original founders of the New Testament—namely, the Apostles, who were instructed immediately by God when he opened their understanding that they might understand the scriptures (Luke 24:25). Therefore, the Apostles were made perfectly knowledgeable and were not instructed by others, but received infused wisdom directly from Christ. In another way, it refers to the future state in heaven, to which the New Testament—but not the Old—brings us. In this sense, what is said here is universally true.

But people in glory are equal to angels, not greater. Yet according to Dionysius, one angel can teach another by enlightening him. Therefore, a person in glory can teach another. I answer that there are two kinds of knowledge in the good angels. The first is what makes them blessed: namely, the knowledge of the divine nature, which alone makes them blessed, as Augustine says in the Confessions: “Blessed is he that knows you.” The second is the knowledge of anything distinct from God, such as God’s works, and this knowledge does not cause blessedness.

Therefore, regarding the first kind of knowledge, one does not teach another, because a person is not made blessed by means of another, but directly by God: In your light we shall see the light (Psalms 35:10). But regarding the other kind, which concerns certain mysteries, one does teach another. This will perhaps continue until the end of the world, as long as the carrying out of God’s works continues. This is why the Apostle adds, know the Lord. This is as if to say that one does not receive knowledge of God from another person. He says, his neighbor and brother, because, according to Augustine, even though all people must be loved out of charity, if you cannot benefit everyone, you should then benefit those who are joined to you, either naturally as blood relatives or by some other tie, such as being your neighbor.

For all shall know me from the least to the greatest of them. This is the reason why one will not teach another: because all will know the Lord. We shall see him as he is (1 John 3:2). And it is in this vision that blessedness consists: This is eternal life: That they may know you, the only true God, and Jesus Christ whom you have sent (John 17:3); Let him that glories, glory in this, that he understands and knows me (Jeremiah 9:24). The blessed receive this teaching not from one another but from God alone: All your children shall be taught of the Lord (Isaiah 54:13).

The phrase from the least to the greatest can be understood in two ways. In one way, the older saints are called “greater,” so that “greater” and “lesser” would be understood according to the order of time. Therefore, all will know God, because each will receive his own penny (Matthew 20:10). Alternatively, he says this to show the different rewards, because although all will know God, one will know Him more than another: He that shall do and teach, he shall be called great in the kingdom of heaven (Matthew 5:19). For the reward corresponds to the merit. This stands against those who say that all punishments and all merits will be equal and, consequently, all rewards. But against this opinion, 1 Corinthians 15:41 states: Star differs from star in glory.

Next, when the Apostle says, because I will be merciful to their iniquities, he states the third effect, which is the remission of guilt, something the Old Testament was unable to do: It is impossible that with the blood of oxen and goats sin should be taken away (Hebrews 10:4). He says, therefore, I will be merciful.

But iniquity differs from sin. Iniquity is opposed to justice, which, strictly speaking, is always directed toward someone else; therefore, iniquity refers to an act by which one person injures another: Your wickedness may hurt a man that is like you (Job 35:8). A sin, however, refers to any defect in an action, because it implies a disorder. Hence, iniquity is, properly speaking, against one’s neighbor, but sin is against oneself. This is the strict definition, but in a broader sense, both are the same.

In this regard, he says, I will be merciful toward their iniquities—that is, in the present life by remitting the punishment—and their sins I will remember no more—that is, in the future, by not punishing them. I will not remember all his iniquities which he has done (Ezekiel 18:22); Forgive us our sins for your name’s sake (Psalms 78:9); Remember not our former iniquities (Psalms 78:8). The gifts and the call of God are without repentance (Romans 11:29); that is, God does not regret having forgiven our sins here, as if He would punish them again later.

Finally, when the Apostle says, in speaking of a new covenant, he argues from the authority he has just cited. He forms this argument: Something is called “new” only in relation to something “old.” But whatever is called old is, by definition, near its end. Therefore, by speaking of a new covenant, he treats the first one as obsolete; that is, he gives us to understand that the former covenant is old. And what is becoming obsolete and growing old is ready to vanish away. Therefore, if it is old, it should be cast out: The new coming on, you shall cast away the old (Leviticus 26:10).

Therefore, by saying a new, he indicates the end of the old. Properly speaking, only what is subject to time can be ancient, and things subject to time eventually cease. Therefore, it is fitting that the old covenant should cease. The Apostle says becoming obsolete in regard to inanimate things, but growing old in regard to living things. It should also be noted that where our text has their sins, another version reads “sin” in the singular. In that case, it would refer to original sin, which is common to all.