Romans 7:18

For. know that in me, that is, in my flesh, dwelleth no good thing: for to will is present with me, but to do that which is good is not. "For. know" -an illustration or explanation of what he has just said.

"in my flesh dwelleth no good thing" -clearly Paul can't be saying that he is wholly evil, for even in this state Paul "desires to do good" (Romans 7:15)

'If "flesh" here means "sinful nature" we would have Paul saying that no good thing dwells in his "sinful nature". Would that be necessary? Wouldn't that be like saying: "that bachelor is an unmarried man?"'

Paul is saying, that outside of Christ, "good" has no permanent dwelling in him. It is erroneous to say that 'Paul didn't or couldn't do one good thing before he became. Christian'. (Acts 23:1; 1 Peter 3:6)

"but to do that which is good is not" -'but the doing of the good is not' (NASV).

'No good thing' gives the impression that Paul is saying he is unable to accomplish even one good act or thought. That isn't what he intends at all (the context reveals that). Of course he can do good things. The "good" that he speaks of in this section is "good" viewed in totality and in relation to Law.'

Paul, as all other's found himself falling short (Romans 3:23) of the demands of Law (Galatians 3:12), he couldn't do good all the time, "goodness" didn't have. permanent abode in him. He contemplated "good", he "willed it", he "desired it", but he didn't ALWAYS perform it.