"Therefore the law was our tutor to bring us to Christ, that we might be justified by faith. But after faith has come, we are no longer under a tutor." (Galatians 3:24, 25)
"What shall we say then? Is the law sin? Certainly not! On the contrary, I would not have known sin except through the law. For I would not have known covetousness unless the law had said, 'You shall not covet.'" (Romans 7:7)
"For whatever things were written before were written for our learning, that we through the patience and comfort of the Scriptures might have hope." (Romans 15:4)
"By faith Abel offered to God a more excellent sacrifice than Cain, through which he obtained witness that he was righteous, God testifying of his gifts; and through it he being dead still speaks." (Hebrews 11:4)