Romans 7:7-8 — What shall we say then? Is the law sin? God forbid. Nay, I had not known sin, but by the law: for I had not known lust, except the law had said, Thou shalt not covet.
But sin, taking occasion by the commandment, wrought in me all manner of concupiscence. For without the law sin was dead.
sin = evil
nay — should read "howbeit"
Thou shalt not covet — The law revealed the evil as such, but also revealed its evil source inside us.
occasion = a military base. The law gave sin a base of operations.
sin was dead — sin as a principle was not active, but the person was still sinful. It's just that the sinfulness of sin wasn't realized. It was torpid, like a snake in the sun, until stirred.
If freed from the Law, then, can we not live in sin? Yes, we can, but shall we? (Romans 6:2, 15). Did we not come to Christ in the first place to be delivered from sin? And did He not die our death so that the "old man" might truly be "a thing of the past"?
But do we not need the Law to help us live aright? No, for God would not have us do His will because we must, or to gain His favor. He, like any normal parent, would have us do His will because we love Him and respond in gratitude to His love for us. Such an attitude needs no law to threaten it. Does a loving mother need a law to make her care for her children? Does a grateful employee need a law to make him serve his employer faithfully?
Without the law sin was dead, Paul continues. As a fallen son of Adam it did not trouble him. And the Law being dead (in him) he was alive, revelling in the "freedom" of doing what he pleased. "But when the commandment came," he says, "sin revived and I died," i.e., the Law made him conscious that sin was alive in him and that he was dead, powerless to deliver himself from it. Thus, he says, "the commandment, which was ordained to life, I found to be unto death (verse 10). C.R. Stam, The Epistle of Paul to the Romans, pg. 165-166.
The law does not cause sin, but in the carnal mind, it provokes sin.