Writers comments on Gal 2:16
16 Knowing that a man is not
justified by the works of the law, but by the faith of Jesus Christ, even we have believed in Jesus Christ, that we might be
justified by the faith of Christ, and not by the works of the law: for by the works of the law shall no flesh be
justified.
The verb “justify” is in the passive voice, thus, literally, it is “to be justified.” It occurs here for the first time in Paul’s epistles, and no less than three times in one verse (v. 16). Justification is not something we do. It is something done for us and given to us freely. It is the gracious act of God, whereby, on the basis solely of Christ’s accomplished mediatorial work, he declares the sinner just.
The work was done by the decree of God in eternity (Rom. 8:29-30). Yes, all God’s elect were in the purpose of God justified from eternity, by the Lamb of God slain from the foundation of the world. Our justification was obtained by Christ when he died at Calvary as our Substitute. He was delivered unto death by the sword of divine justice because of our sins imputed to him, and raised again by the glory of God because of our justification accomplished by his sacrifice (Rom. 4:25). Faith in Christ does not accomplish justification, but receives it as the free grace gift of God (Rom. 5:1, 10-11; 8:1, 30, 33; Tit. 3:7).
Faith in Christ is not a condition upon which justification is granted, but one of the many, blessed fruits of justification accomplished. It is not our faith that justifies us, but Christ who is the Object of our faith.
Justification is a judicial act of God. It does not come as the result of man’s effort (Rom. 3:20, 28; Gal. 3:11; 5:4). It is not even the result of faith (Eph. 2:8). It took place when Christ satisfied the demands of the law as a Substitute for his elect (Rom. 3:24; 2 Cor. 5:21; Eph. 1:7). Man can never earn it. He only receives it by faith. And even the faith by which we receive it is the gift of God’s grace (Eph. 2:8). “Man is not justified by the works of the law, but by the faith of Jesus Christ.
https://www.grace-ebooks.com/library/Don Fortner/DF_Discovering Christ In Galatians.pdf 34