Let not sin therefore reign in your mortal body, that you should obey it in its lusts.
Read Chapter 6
Ambrosiaster
AD 400
The body is mortal because of the sin of Adam, but by faith in Christ we believe that it will be immortal. But in order for it to inherit the promise, Paul says that it must not listen to the voice of sin, so that sin may not reign in our mortal body. For it reigns as long as it is in control. But if it does not reign, the body will no longer appear to be mortal, because it dwells in the hope of eternal life. Paul did not say that the body is mortal because it will disintegrate but because of the pain of hell, so that the man who is sent to hell is said to be mortal because whoever hearkens to sin will not escape the second death, from which the Savior has delivered those who believe in him. Therefore, the mortal body refers to the entire human being because those who hearken to sin are said to be mortal. For Scripture says: “The soul which sins shall surely die,” which means the whole human being. For nobody will be judged apart from his body. Commentary on Paul’s Epistles.
We must engage in a constant, daily struggle not to obey those desires which are forbidden or improper. For from this sort of fault it comes about that the eye is turned to where it ought not to look, and if this fault grows strong and prevails, even bodily adultery is carried out, which is committed in the heart as much more quickly as thought is quicker than action and has nothing to hinder or delay it.
The reign of sin is overthrown and destroyed, partly by such an amendment on the part of men that the flesh is made subject to the spirit and partly by the condemnation of those who are persevering in sin, in order that they might be so justly restrained that they cannot be troublesome to the righteous, who reign with Christ. Commentary on the Lord’s Sermon on the Mount.
Here Paul shows that the reason we no longer sin is not that after baptism we are no longer made of flesh. Up to this point, we claim Christ’s perfection by faith only and not by experience. For we have not yet become impassible or immortal…. Therefore Paul does not say: “Do not sin,” but rather: “Let not sin reign in your mortal bodies.” .
Let not sin, therefore, reign He compares sin and justice to two kings, or generals, under one of which every man fights in this world. Sin is the tyrant, under which fight the wicked, and make their minds and their members the instruments, or arms of iniquity to sin, when they follow and yield to their disorderly lusts. But he exhorts them to live so as to make the powers of their souls, and their members, instruments or arms of justice to God, to fight under God, their lawful king, and under the banner of his justice. (Witham)
In these same members in which we used to serve sin and bring forth fruit unto death, God wants us to be obedient unto righteousness, that we may bring forth fruit unto life. .
And for this reason he says, in the Epistle to the Romans: "Let not sin, therefore, reign in your mortal body, to be under its control: neither yield ye your members instruments of unrighteousness unto sin; but yield yourselves to God, as being alive from the dead, and your members as instruments of righteousness unto God."
It is absurd for those who are being led toward the kingdom of God to have sin ruling over them or for those who are called to reign with Christ to choose to be captives to sin, as if one should throw down the crown from off his head and choose to be the slave of a hysterical woman who comes begging and covered in rags. … How is it that sin can reign in you? It is not from any power of its own but only from your laziness.
After showing that we ought not remain in sin [n. 470] and that we have the faculty for this [n. 478], the Apostle concludes with a moral exhortation. And concerning this he does three things: 249 first, he proposes an admonition; secondly, he assigns a reason [v. 14; n. 496]; thirdly, he raises and solves a question [v. 15; n. 499]. In regard to the first he does two things: first, he proposes the admonition; secondly, he clarifies [v. 12b; n. 494]. 493. First, therefore, he says: We have said that our old self was crucified once, so that the body of sin may be destroyed. This means that the power of sin has been so weakened that it cannot rule us. Therefore, let not sin reign in your mortal bodies any longer. He does not say: Let not sin be in your mortal body, because as long as our body is mortal, it is not possible for sin not to be in our body, i.e., the inclination to sin. But since we have been freed from the kingdom of sin by God, we must struggle in order that sin not recover...
