Verse 14 serve both as a conclusion and as a transition. It is a conclusion to Paul’s argument in the first part of the chapter, and it serves as a transition to a more detailed discussion in the rest of the chapter and in chapter 7. In Greek sin must not rule over you is a future tense (Revised Standard Version “sin will have no dominion over you”), but in the context its force is imperative. The reason that sin must not rule over the believer is that he does not live under law but under God’s grace. Paul looks upon the law as giving sin a free hand and contributing to its strength (see 5.20-21). Moreover, law and sin are related not only on this basis, but on the basis that law is symbolic of man’s strivings by his own efforts to put himself right with God. God’s grace (literally “grace”), on the other hand, delivers a man from sin, because it depends not on the human will or on human strength, but on the divine activity.

The initial clause sin must not rule over you may be construed as a matter of permission—for example, “you must not permit sin to command you.” The final clause of verse 14 may be regarded as the reason for not permitting sin to rule over a person—for example, “because you do not live under law but under God’s grace” or “because you do not live by what the law tells you you must do, but by the goodness which God has shown you.”

Quoted with permission from Newman, Barclay M. and Nida, Eugene A. A Handbook on Paul’s Letter to the Romans. (UBS Handbook Series). New York: UBS, 1973. For this and other handbooks for translators see here .