to be lord or master of; to hold dominion over someone or something
The verb is built straight from the noun for "lord" or "master" (kurios), and it means to act as that lord: to hold and exercise dominion over a person or thing. On its own it carries no praise or blame. Whether the rule is good or evil, rightful or cruel, depends entirely on who is doing the ruling.
That single fact drives its use in the New Testament. The same word describes a hostile power holding people in its grip (sin and death), a human king ruling his subjects, the law binding a person for as long as they live, and Christ reigning as the rightful Lord of both the dead and the living. Paul even reaches for it to describe himself, only to deny it: he refuses to "lord it over" anyone's faith. A fuller, stronger form of the same idea, κατακυριεύω, turns up wherever the control is heavy-handed, and the plain verb is often paired with the word for reigning as a king, βασιλεύω, as in the title "King of kings and Lord of lords."
Because the word itself is neutral, salvation in Paul's letters looks less like the end of all mastery and more like a change of masters. When he promises that sin "will not have dominion over you," he is announcing a transfer of ownership, out of the hands of an illegitimate lord and into the hands of the true one.
Nuances
Whether the law's rule over a person in Romans 7:1 is meant as legitimate, temporary legal authority (jurisdiction that lapses at death) or as one more hostile power holding people in bondage alongside sin and death.
- majorityThe law here has ordinary binding legal authority over a person for as long as they live, like any law over its subjects; it is legitimate and temporary, not evil.; C.E.B. Cranfield, Romans (ICC, 1975-1979), 1:332-333; Douglas J. Moo, The Epistle to the Romans (NICNT, 2nd ed. 2018); Thomas R. Schreiner, Romans (BECNT, 2nd ed. 2018)
- minorityThe law belongs with sin and death as an enslaving power of the old order, so its rule is of the same oppressive kind.; Ernst Kasemann, Commentary on Romans (ET Bromiley, Eerdmans 1980), 187-189