^5:20 Now the law entered in that sin might abound. [n. 448] And where sin abounded, grace did more abound. [n. 464]
^5:21 That as sin has reigned to death: so also grace might reign by justice unto life everlasting, through Jesus Christ our Lord. [n. 467]

448. After showing that through the gift of grace sin is removed, which entered this world through Adam, the Apostle now shows that through Christ’s grace is taken away the sin that increased when the law came.

Concerning this he does two things.

First, he mentions the increase of sin through the law;

second, the absolution of sin through Christ’s grace, at and where sin abounded.

449. First, therefore, he says: it has been stated that through the obedience of one man many are made just. However, it was not the law that could achieve this; rather, the law entered in that sin might abound.

450. Two problems arise from these statements of the Apostle.

First, from the statement that the law entered in, i.e., entered secretly, after original and actual sin or after the natural law, as the Gloss says. For the law did not come in secretly but was given openly, in accord with John: I have not spoken in secret (John 18:20).

The answer is that although the legislation had been given openly, the mysteries of the law were hidden, especially in regard to God’s intention in promulgating the law, which would point out sin without healing it: for who has known the mind of the Lord? (Rom 11:34).

It can also be said that the law entered, i.e., entered into the middle, so to speak, between man’s sin and the gift of Christ’s grace, each of which he had said above passed from one to many.

451. The second problem arises from the statement that the law came in that sin might abound.

For this would seem to make increase of sin the purpose of the law; consequently, the law would be evil, because a thing whose purpose is evil is itself evil. But this is contrary to the statement in 1 Timothy: we know that the law is good (1 Tim 1:8).

452. A Gloss answers this in three ways.

First, that the word that should be taken as indicating not a causal connection but a mere sequence. For the law was not given in order that sins might increase; rather, the law, as far as in it lay, forbade sin: I have laid up your word in my heart, that I might not sin against you (Ps 119:11). But, once the law was given, increase of sin followed in two ways.

453. In one way, as to the number of sins. For although the law pointed out sin, it did not take away desire for sin. Indeed, when someone is forbidden what he desires, he burns with a stronger desire for it, as a torrent flows with greater force against an obstacle erected against it and finally breaks it.

454. There can be three reasons for this.

First, because when something is subject to a man’s power he does not consider it anything great, whereas he perceives a thing beyond his power as great. But a prohibition against something desired puts that thing, as it were, beyond man’s power; consequently, the desire for it increases as long as it is prohibited.

The second reason is that internal affections, when they are kept within and permitted no outlet, burn the more strongly within. This is clear in sorrow and anger which, when they are kept within, continually increase; but if they are given any kind of release outwardly, their vigor is dissipated. But a prohibition, since it threatens a penalty, compels man not to give outward expression to his desire, so that, being kept within, it burns more vigorously.

The third reason is that anything not forbidden is regarded as something possible to do any time it pleases us; therefore, even when the opportunity is present, we often avoid doing it. But when something is forbidden, we see it as something we may not always have; therefore, when the opportunity arises to obtain it without fear of punishment, we are readier to seize it.

455. These, then are the reasons why in the face of the law, which forbade acts of concupiscence and yet did not mitigate that concupiscence, the concupiscence itself leads men more feverishly toward sin. Hence, it is said, this is Jerusalem; I have set her in the center of the nations, with countries round about her. She wickedly rebelled against my ordinances more than the nations (Ezek 5:5).

456. But according to this it seems that every human law, which of course does not confer grace to lessen concupiscence, would make sin increase. However, that seems to be against the lawgiver’s intention, because his aim is to make the citizen good, as the Philosopher says in Ethics II.

The answer is that the intention of human law is one thing and that of divine law another. For human law is subject to human judgment, which is concerned with external acts; but the divine law is subject to divine judgment, which is concerned with the inward movement of the heart, as is said, man looks on the outward appearance, but God looks at the heart (1 Sam 16:7). Accordingly, human law achieves its aim when by means of prohibitions and threats of punishment it prevents external sinful acts, even though the inward concupiscence increases more. But as far as the divine law is concerned, it imputes as sin even the inward evil desires, which increase when the law forbids them without destroying them.

457. Yet it should be noted, as the Philosopher says in Ethics X, that although a legal prohibition restrains the ill disposed from outward sins by the fear of punishment, it nevertheless guides the well disposed through love of virtue. Now that good disposition is present to a certain extent by nature, although its perfection is achieved only by grace. Consequently, even after the old law had been given, sin did not increase in all but in the majority. But some, guided by the law’s prohibitions and further strengthened by grace, reached the heights of virtue: let us now praise glorious men . . . men great in virtue (Sir 44:1).

458. Second, with the coming of the law sin abounded as far as the weight of guilt was concerned. For sin was more grievous when it became a transgression not only of the law of nature but also of the written law. Hence it was said above that where there is no law, neither is there transgression (Rom 4:15).

459. A second answer is that the word that can be taken causally but in the sense that the Apostle is speaking of sin’s increase as far as our knowledge of it is concerned. As if to say: law entered in that sin might abound, i.e., that sin might be more abundantly known, according to the manner of speaking whereby something is said to come to pass when it is recognized. Hence, he said above that by the law is the knowledge of sin (Rom 3:20).

460. The third answer also takes that in a causal sense, but not as meaning that increase of sin is the goal of the law’s entering in, but what results from sin’s increase, namely, man’s humiliation.

For after the law came in, sin abounded, as was said in the first explanation. The consequence of this increase of sin was that man, recognizing his weakness, was humbled. For the proud man, presuming on his own strength, said: there is no lack of doers, but of commanders, in accord with Exodus, all that the Lord has spoken we will do and will be obedient (Exod 24:7). But when, after the law had been given, the number of sins increased, men recognized how weak they were in observing the law: man is weak and short-lived, with little understanding of judgment and laws (Wis 9:5).

Therefore, God’s intention in giving the law is not aimed at increasing sin but at man’s humility, for the sake of which he permitted sin to abound. Accordingly, because this purpose was hidden, he says that the law entered in secretly.

461. Since we are dealing with the law and the end of the law, two things propose themselves for consideration. First, the number of senses of the word ‘law’; second, what is the end of the law.

462. In regard to the first it should be noted that ‘law,’ taken one way, names the entire scripture of the Old Testament; for example, John says, it is to fulfill the word that is written in the law, that now they have sin and hated both me and my Father (John 15:25), when this was written in a psalm (Ps 24:19). But sometimes the ‘law’ refers to the five books of Moses, in accord with Deuteronomy, Moses commanded us a law (Deut 33:4). Third, the precepts of the Decalogue are called the ‘law’: I will give you the tables of stone, with the law and commandment, which I have written for their instruction (Exod 24:12). Fourth, the entire content of the ceremonial precepts is called the ‘law,’ as in Hebrews, since the law has but a shadow of the good things to come (Heb 10:1). Fifth, any definite ceremonial precept is called a ‘law,’ as in Leviticus: this is the law of the sacrifice of peace offerings (Lev 7:11).

But in this section of the epistle, the Apostle takes ‘law’ in a general way, i.e., as referring to the total doctrine of the Mosaic law, namely, the moral and ceremonial precepts, because through the ceremonies of the law grace was not given to help man fulfill the precepts and to reduce concupiscences.

463. In regard to the end of the law it should be noted that among the Jewish people, as among every people, there were three kinds of men: the obstinate, i.e., sinners and rebels, the proficient, and the perfect.

With respect to the obstinate the law was given as a scourge both as to the moral precepts to whose observance they were compelled by threats of punishment, as is evident from Leviticus 2, and as to the ceremonial precepts, which were multiplied to prevent them from cultivating alien gods: with a strong hand and outstretched arm, and with anger poured out I will rule over you (Ezek 20:34).

For the proficient, who are called the ordinary people, the law was a pedagogue: the law was our pedagogue in Christ (Gal 3:24). It was so with respect to the ceremonial precepts, by which they were restrained in divine worship, and with respect to the moral precepts, by which they were advanced toward justice.

For the perfect the law regarding ceremonies was a sign: I gave them my sabbaths, as a sign between me and them, that they might know that I the Lord sanctify them (Ezek 20:12); the law regarding morals acted as a consolation, as expressed below: I am delighted with the law of God (Rom 7:22).

464. Then when he says, where sin abounded, he shows how increase of sin was taken away by grace.

First, he sets out that grace abounded;

second, the effect of abounding grace, at that as sin has reigned.

465. First, therefore, he says: it has been stated that with the coming of the law sin abounded. But this was no obstacle to the divine plan for the salvation of the Jews and of the whole human race, because where sin abounded, namely, in the human race and especially among the Jews, grace did more abound, namely, the grace of Christ forgiving sins: God is powerful to make every grace abound in you (2 Cor 9:8).

466. Two reasons can be given for what is said here.

One is based on the effect of grace. For just as the enormity of a disease is not cured except by a strong and effective medicine, so an abundant grace was required to heal the abundance of sins: many sins are forgiven her, for she has loved much (Luke 7:47).

The other reason is based on the attitude of the sinner. Some, realizing the enormity of their sins, give way to despair and contempt: when wickedness comes, contempt comes also (Prov 18:3); others by the help of divine grace are humbled when they consider their sins and so obtain a greater grace: their infirmities were multiplied; afterwards they made haste (Ps 16:4).

467. Then when he says that as sin has reigned to death, he shows the effect of abundant grace, an effect that corresponds by way of opposition to that of sin.

That as sin, introduced by the first man and abounding through the law, has reigned, i.e., obtained complete dominion over men, and this until it brought them to death both temporal and eternal: the wages of sin is death (Rom 6:23), so also grace, i.e., God’s grace, might reign, i.e., rule entirely in us, by justice, which it produces in us: they are justified by his grace (Rom 3:24). And this until it brings us unto life everlasting: the free gift of God is eternal life (Rom 6:23).

And all of this is through Jesus Christ our Lord, who is the giver of grace: grace and truth came through Jesus Christ (John 1:17). He is justice: whom God made our justice (1 Cor 1:30); and he is the giver of eternal life: I give them eternal life (John 10:28).