Salvation isn't accessed in OT Mosaic law keeping.
It's accessed thru FAITH placed Jesus's death & resurrection. 1 Cor 15:1-4, Rom 5:1-2. 10:9, Eph 1:7,13,14, 2:8-9
Galatians 3:
6 Even as Abraham believed God, and it was accounted to him for righteousness.
(NOTE: Abraham believed God & God declared Abraham righteous thru FAITH, not works)
7 Know ye therefore that they which are of faith, the same are the children of Abraham.
(MY NOTE: Everyone the puts their FAITH in Christ's sin payment & resurrection is a child of Abraham & declared righteous by God)
8 And the scripture, foreseeing that God would justify the heathen through faith, preached before the gospel unto Abraham, saying, In thee shall all nations be blessed.
(MY NOTE: 430 yrs before the Law to Moses (Gal 3:17). God promises Abraham ALL gentile/nations would be justified thru Faith (see justification KJB dictionary below)
9 So then they which be of faith are blessed with faithful Abraham.
(MY NOTE: We receive the same justification blessing as Abraham did thru FAITH)
10 For as many as are of the works of the law are under the curse: for it is written, Cursed is every one that continueth not in all things which are written in the book of the law to do them.
(MY NOTE: If doing works of law keeping is your litmus test for accessing righteousness/justification. You are cursed/condemned in God's sight)
11 But that no man is justified by the law in the sight of God, it is evident: for, The just shall live by faith.
(See MY NOTE vs 10 & here The just shall live by FAITH)
13 Christ hath redeemed us from the curse of the law, being made a curse for us: for it is written, Cursed is every one that hangeth on a tree:
(MY NOTE: A sinless Christ took our due judgment paying sins required wage (Rom 6:23).
14 That the blessing of Abraham might come on the Gentiles through Jesus Christ; that we might receive the promise of the Spirit through faith.
(MY NOTE: Thru FAITH/trust placed in Christ' payment & resurrection. Believers receive God's promise: Lk 24:49, Acts 1:4, 5, 2:4, 33. The baptism of Christ's salvation sealing: (2 Cor 1:22, 5:5, 2 Tim 1:14, Eph 4:30) forever indwelling Holy Spirit)
15 Brethren, I speak after the manner of men; Though it be but a man's covenant, yet if it be confirmed, no man disannulleth, or addeth thereto.
(MY NOTE: Scripture proclaims here, this promise of righteousness once confirmed thru FAITH can't be annulled)
16 Now to Abraham and his seed were the promises made. He saith not, And to seeds, as of many; but as of one, And to thy seed, which is Christ.
17 And this I say, that the covenant, that was confirmed before of God in Christ, the law, which was four hundred and thirty years after, cannot disannul, that it should make the promise of none effect.
(MY NOTE: 430 & yrs before the Law to Moses. God made Abraham a promise & the Mosaic law covenant doesn't change or annul God's Abrahamic promise)
KJV Dictionary Definition: JUSTIFICATION; (4) In theology, remission of sin and absolution from guilt and punishment; or an act of free grace by which God pardons the sinner and accepts him as righteous, on account of the atonement of Christ.
JUSTIFICATION - Definition from the KJV Dictionary
(MY NOTE: ABSOLUTION from GUILT & PUNISHMENT. Believers are JUSTIFIED = Judicially Declared Righteous by a sovereign God. Righteousness is an imputed free Gift (Rom 5:17). Imputed thru Faith placed in Jesus FINISHED sin atoning sacrifice & resurrection. Thru Faith & faith alone, we become justified/righteous/SAVED the "MOMENT" we believe in Christ's sin payment & resurrection. Jesus did ALL the work necessary & all we need to do is TRUST Him!)