If you are asking if one can be saved by keeping the law the answer is no. My logic here is that Jesus Christ was a perfect man without sin but he was never a man who needed to be saved to attain that perfection. though he was tempted in all points like as we are, yet without sin. He was an innocent man from his birth and never became guilty though he willingly accepted the guilt penalty of sin for every man, which is death. Because he had no personal guilt God raised him from the dead and has promised to pardon every one who will receive the pardon by faith from him who raised him from the dead and who is also the Judge of all the earth. This is stated emphatically.
Ro 4:20 He (Abraham) staggered not at the promise of God through unbelief; but was strong in faith, giving glory to God;
21 And being fully persuaded that, what he (God the Father) had promised, he (God the Father) was able also to perform.
22 And therefore it (Abraham's faith) was imputed to him for righteousness.
23 ¶ Now it was not written for his sake alone, that it (righteousness) was imputed to him;
24 But for us (now since the cross) also, to whom it (righteousness) shall be imputed, (what is the condition?) if we believe on him (God the Father) that raised up Jesus our Lord from the dead;
25 Who was delivered for our offences, and was raised again for our justification.
Ga 3:12 And the law is not of faith: but, The man that doeth them shall live in them.
Ga 3:21 Is the law then against the promises of God? God forbid: for if there had been a law given which could have given life, verily righteousness should have been by the law.
Abraham could not have been saved by believing what God said to us about his son and resurrection from the dead. Neither could anyone living today be justified by God, the Judge, by believing what Abraham believed that justified him. The text of Romans 4 says clearly what Abraham believed.
So faith itself is non dispensational. It, faith in what God says, is the principle of justification throughout all the ages. It is not, one and the same message from God fits all, that justifies, it is believing what God says to us. In this age God has said this to the whole world. This is what everyone must now believe to be justified.
Acts 17:16 ¶ Now while Paul waited for them at Athens, his spirit was stirred in him, when he saw the city wholly given to idolatry.
17 Therefore disputed he in the synagogue with the Jews, and with the devout persons, and in the market daily with them that met with him.
18 Then certain philosophers of the Epicureans, and of the Stoicks, encountered him. And some said, What will this babbler say? other some, He seemeth to be a setter forth of strange gods: because he preached unto them Jesus, and the resurrection.
19 And they took him, and brought him unto Areopagus, saying, May we know what this new doctrine, whereof thou speakest, is?
20 For thou bringest certain strange things to our ears: we would know therefore what these things mean.
21 (For all the Athenians and strangers which were there spent their time in nothing else, but either to tell, or to hear some new thing.)
22 ¶ Then Paul stood in the midst of Mars’ hill, and said, Ye men of Athens, I perceive that in all things ye are too superstitious.
23 For as I passed by, and beheld your devotions, I found an altar with this inscription, TO THE UNKNOWN GOD. Whom therefore ye ignorantly worship, him declare I unto you.
24 God that made the world and all things therein, seeing that he is Lord of heaven and earth, dwelleth not in temples made with hands;
25 Neither is worshipped with men’s hands, as though he needed any thing, seeing he giveth to all life, and breath, and all things;
26 And hath made of one blood all nations of men for to dwell on all the face of the earth, and hath determined the times before appointed, and the bounds of their habitation;
27 That they should seek the Lord, if haply they might feel after him, and find him, though he be not far from every one of us:
28 For in him we live, and move, and have our being; as certain also of your own poets have said, For we are also his offspring.
29 Forasmuch then as we are the offspring of God, we ought not to think that the Godhead is like unto gold, or silver, or stone, graven by art and man’s device.
30 And the times of this ignorance God winked at; BUT NOW commandeth all men every where to repent:
31 Because he hath appointed a day, in the which he will judge the world in righteousness by that man whom he hath ordained; whereof he hath given assurance unto all men, in that he hath raised him from the dead.
32 ¶ And when they heard of the resurrection of the dead, some mocked: and others said, We will hear thee again of this matter.
33 So Paul departed from among them.
34 Howbeit certain men clave unto him, and believed: among the which was Dionysius the Areopagite, and a woman named Damaris, and others with them.
I hope you can understand this. No one before the resurrection could be justified by believing it because it was not a literal fact until then. Now, since it has actually happened, no one on the planet can be justified and counted righteous on the merits of Jesus unless they believe his gospel and the promise of God that he will save all who come s to him through Jesus Christ.
One must believe the words of God that are given to him.