The natural man lives in sin like a fish lives in water. Take him out, and he flops back into it. In regeneration, this natural man–a sinner–dies and is born again as a Christian. A Christian can no longer live in sin, no more than a reptile could live underwater.
The Gospel calls for a radicalized people willing to die for it. Would you rather die than get mad, get drunk, or fornicate? Would you rather die than commit any sin? Are you giving up your life right now to the work of the Gospel?