Galatians 2:16-21 (NKJV)
16 Knowing that a man is not justified by the works of the law but by faith in Jesus Christ, even we have believed in Christ Jesus, that we might be justified by faith in Christ and not by the works of the law; for by the works of the law no flesh shall be justified.
17 But if, while we seek to be justified by Christ, we ourselves also are found sinners, is Christ therefore a minister of sin? Certainly not!
18 For if I build again those things which I destroyed, I make myself a transgressor.
19 For I through the law died to the law that I might live to God.
20 I have been crucified with Christ; it is no longer I who live, but Christ lives in me; and the life which I now live in the flesh I live by faith in the Son of God, who loved me and gave Himself for me.
21 I do not set aside the grace of God; for if righteousness comes through the law, then Christ died in vain.