Re: Romans 7:18-20. You said, “Paul sinned because he was a sinner. It was his nature to sin, and it’s ours too.” You have also said, “God knows that no matter how hard we try, we’ll fail to meet His righteous standard because we’re flawed. Our sin nature will always betray us.” Does this mean that Jesus also had a sin nature, and that He overcame it? Or did He just not have a sin nature?
One of the great mysteries of the Bible is that the sin nature is apparently passed from father to child. Although females have a sin nature, they don’t pass it along. Jesus, having no earthly father, did not have a sin nature even though he had an earthly mother. He was without sin, the only man in history to be so, and therefore the only one who could qualify to save us.
“For we do not have a high priest who is unable to sympathize with our weakness, but we have one who was tempted in every way – yet was without sin.” (Hebrews 4:15)