But sin, taking occasion by the commandment, wrought in me all manner of concupiscence. For without the law sin was dead.
But sin (i:e., my indwelling corruption), taking occasion by the commandment, wrought in me all manner of concupiscence, х epithumian (G1939)]. Here the same Greek word is unfortunately rendered by three different English ones - "lust," "covet," "concupiscence" - which obscures the meaning. By using the word "lust" only-in the wide sense of all 'irregular desire,' or every out-going of the heart toward anything forbidden-the sense will best be brought out thus: 'For I had not known lust, except the law had said, Thou shalt not lust. But sin, taking occasion by the commandment (that commandment which expressly forbids it) wrought in me all manner of lusting.' See Proverbs 9:17, "Stolen waters are sweet, and bread eaten in secret is pleasant." Compare also the well-known saying of Horace, Nitimur in vetitum nefas, cupimusque negata. This gives a deeper view of the tenth commandment than the mere words suggest. The apostle saw in it the prohibition not only of desire after certain things there specified, but of 'desire after everything divinely forbidden;' in other words, all 'lusting' or 'irregular desire.' It was this which "he had not known but by the law." The law forbidding all such desire so stirred his corruption that it worked in him "all manner of lusting" - desire of every sort after what was forbidden.
For without the law - i:e., Before its extensive demands and prohibitions come to operate upon our corrupt nature, Sin [was] (rather, 'is') dead - i:e., the sinful principle of our nature lies so dormant, so torpid, that its virulence and power are unknown, and to our feeling it is as good as "dead."