Notice that what Paul says in Romans is drawing a contrast between Christ and the Commandments of the Law :
Romans 10:5-9 For Moses writes about the righteousness that is based on the law, that the person who does the commandments shall live by them. But the righteousness based on faith says, "Do not say in your heart, 'Who will ascend into heaven?'" (that is, to bring Christ down) or "'Who will descend into the abyss?'" (that is, to bring Christ up from the dead). But what does it say? "The word is near you, in your mouth and in your heart" (that is, the word of faith that we proclaim); because, if you confess with your mouth that Jesus is Lord and believe in your heart that God raised him from the dead, you will be saved.
Salvation and life by belief and confession, not by keeping the Law.
You will accuse again, 'trying to make excuse for sin' but that is just a straw man. It's about what is true, and the truth is that salvation is not by works, but by grace through belief in the Son of God who did the work, and works still in everyone whose trust is in Him rather than anything else.
Keeping a Law I have already broken does not save me. I am already guilty. Nothing I can do will take away that guilt. It remains until a greater power than I removes it. I believe Jesus to be that greater power.
If I truly believe Jesus is that greater power, then I will listen to Him, and I will do as He instructed.
Rom. 10:
5 For Moses describeth
the righteousness which is of the law, That
the man which doeth those things shall live by them.
God gave Moses "works" for a man to do which were to take away his sins, (Until the Seed should come) therefore saving him from death. A man that did these "works" lived by doing them. Failure to follow this "Law of works" resulted in no Salvation.
We
were to take a goat or turtle dove to the Levite Priest, and he would perform sacrificial "Works" to atone for our sins. It's in your Bible.
This is the "Righteousness which is of the Law" This is the "LAW of Works" Paul spoke of in Rom 3, and again in Galatians.
But the Law of Faith Abraham had, that Jesus followed and taught, that God judges the whole world with.
Paul chose to Quote Deuteronomy to make his point.
Duet. 30:
10 If thou shalt hearken unto the voice of the LORD thy God, to keep his commandments and his statutes which are written in this book of the law,
and if thou turn unto the LORD thy God with all thine heart, and with all thy soul.
11 For this commandment which I command thee this day,
it is not hidden from thee, neither is it far off.
12 It
is not in heaven, that thou shouldest say, Who shall go up for us to heaven,
and bring it unto us, that we may hear it, and do it?
13 Neither
is it beyond the sea, that thou shouldest say, Who shall go over the sea for us,
and bring it unto us, that we may hear it, and do it?
14 But the word is very nigh unto thee, in thy mouth, and in thy heart, that thou mayest do it.
15 See,
I have set before thee this day life and good, and death and evil;
16 In that I command thee this day to
love the LORD thy God,
to walk in his ways, and
to keep his commandments and his statutes and his judgments,
that thou mayest live and multiply: and the LORD thy God shall bless thee in the land whither thou goest to possess it.
This is the Lord I believe. He has Laws and requirements. Any other Lord is a imposter, IMO.