righteousness is by faith, keeping the law does not make us saved.
Rom 3:31 Do we then make void the law through faith? God forbid: yea, we establish the law.
Rom 6:1 What shall we say then? Shall we continue in sin, that grace may abound?
Rom 7:6 But now we are delivered from the law, that being dead wherein we were held; that we should serve in newness of spirit, and not in the oldness of the letter.
We are delivered by the death of Jesus, His blood makes us clean from the transgression of the law. But does that mean we can continue in sin?
Rom 7:7 What shall we say then? Is the law sin? God forbid. Nay, I had not known sin, but by the law: for I had not known lust, except the law had said, Thou shalt not covet.
No law = no sin.
Rom 7:8 But sin, taking occasion by the commandment, wrought in me all manner of concupiscence. For without the law sin was dead.
Rom 7:9 For I was alive without the law once: but when the commandment came, sin revived, and I died.
Rom 7:10 And the commandment, which was ordained to life, I found to be unto death.
Rom 7:11 For sin, taking occasion by the commandment, deceived me, and by it slew me.
Rom 7:12 Wherefore the law is holy, and the commandment holy, and just, and good.
Rom 7:13 Was then that which is good made death unto me? God forbid. But sin, that it might appear sin, working death in me by that which is good; that sin by the commandment might become exceeding sinful.
Rom 7:14 For we know that the law is spiritual: but I am carnal, sold under sin.
This tells me the law is still valid for us to understand sin today.