Let not sin therefore reign in your mortal body, that ye should obey it in the lusts thereof. Let not sin therefore reign - This is a prosopopoeia, or personification. Sin is represented as a king, ruler, or tyrant, who has the desires of the mind and the members of the body under his control so that by influencing the passions he governs the body. Do not let sin reign, do not let him work; that is, let him have no place, no being in your souls; because, wherever he is he governs, less or more: and indeed sin is not sin without this. How is sin known? By evil influences in the mind, and evil acts in the life. But do not these influences and these acts prove his dominion? Certainly, the very existence of an evil thought to which passion or appetite attaches itself, is a proof that there sin has dominion; for without dominion such passions could not be excited. Wherever sin is felt, there sin has dominion; for sin is sin only as it works in action or passion against God. Sin cannot be a quiescent thing: if it do not work it does not exist.
That ye should obey it in the lusts thereof - Αυτῃ εν ταις επιθυμιαις αυτου. This clause is wanting in the most ancient and reputable MSS. and in the principal versions. Griesbach has left it out of his text; and Professor White says, Certissime delenda: "These words should certainly he expunged" they are not necessary to the apostle's argument; it was enough to say, Let not sin reign in your mortal bodies, that ye should obey it. If it be there it will reign there; and its reign supposes, necessarily, the subjection of that in which it reigns. A king reigns when his laws are enforced, and the people obey them. When there is no executive government there is no reign. There may be a royal shadow there, but there is no king.