But when I saw that they walked not uprightly according to the truth of the gospel, I said unto Peter before them all, If thou, being a Jew, livest after the manner of Gentiles, and not as do the Jews, why compellest thou the Gentiles to live as do the Jews? We who are Jews by nature, and not sinners of the Gentiles, 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. But if, while we seek to be justified by Christ, we ourselves also are found sinners, is therefore Christ the minister of sin? God forbid. For if I build again the things which I destroyed, I make myself a transgressor. For I through the law am dead to the law, that I might live unto God. I am crucified with Christ: neverthless I live; yet not I, but Christ liveth in me: and the life which I now live in the flesh I live by the faith of the Son of God, who loved me, and gave himself for me.
St. John Chrysostom in his Commentary on Galatians, Ch. II said:
“Observe how cautiously he expresses himself; he does not say that they had abandoned the Law as evil, but as weak. If the law cannot confer righteousness, it follows that circumcision is superfluous; and this far he now proves, but he proceeds to show that it is not only superfluous but dangerous …He speaks more strongly …If faith in Him, he says, does not avail for our justification, and should it be necessary to embrace the law again, having forsaken the law for Christ’s sake, we are not justified but condemned for such abandonment. Then will we find Him, for whose sake we forsook the law and went over to faith …Observe how he has resolved the matter to a necessary absurdity …Observe the Apostle’s discernment. His opponents tried to show that one who did not keep the law was a transgressor, but he reverts the argument against them and shows that the one who did keep the law was a transgressor, not merely of faith, but of the law itself …He means this: the law has confessedly ceased, and we have abandoned it and betaken ourselves to the salvation which comes of faith. But if we make a point of setting it up again, we become by that very act transgressors, striving to keep what God has annulled …He adds the cause of living, and shows that when alive, the law slew Him, but that when dead, Christ through death restored him to life.”
“He shows the wonder to be twofold: that by Christ both the dead was begotten into life, and that by means of death. He means here immortal life, for this is the meaning of the words, ‘That I might live to God I have been crucified with Christ.’ How, it is asked, can a man now living and breathing have been crucified? …It is Baptism He alludes to …our subsequent manner of life, whereby our members are mortified. By saying, ‘Christ lives in me,’ he means nothing is done by me which Christ disapproves; for as by death he signifies not what is commonly understood, but a death to sin, so by life, he signifies a delivery from sin. For a man cannot live to God otherwise than by dying to sin, and as Christ suffered bodily death, so does Paul experience a death to sin (Cf. Col. 3:5) …As sin, when it has the mastery, is itself the vital principle, and leads the soul wherever it will, so, when it is slain and the will of Christ is obeyed, this life is no longer earthly, but Christ lives, that is, works, has mastery within us.”
Origen in his Commentary on Matthew Book XII said:
“…let every thought and every purpose and every word and every action become a denial of ourselves, but a testimony about Christ and in Christ; for I am persuaded that every action of the perfect man is a testimony to Christ Jesus, and that abstinence from every sin is a denial of self, leading him after Christ. And such an one is crucified with Christ, and taking up his own cross follows Him who for our sakes bears His own cross, according to that which is said in John: ‘They took Jesus therefore and put it on Him,’ etc., down to the words, ‘Where they crucified Him.’ (Jn. 19:17-18) But the Jesus according to John, so to speak, bears the cross for Himself, and bearing it went out; but the Jesus according to Matthew and Mark and Luke, does not bear it for Himself, for Simon of Cyrene bears it. And perhaps this man refers to us, who because of Jesus take up the cross of Jesus, but Jesus Himself takes it upon Himself; for there are, as it were, two conceptions of the cross, the one which Simon of Cyrene bears, and the other which Jesus Himself bears for Himself…also each of those who have been crucified with Christ puts off from himself the principalities and the powers, and makes a show of them and triumphs over them in the cross; (Col. 2:15) or rather, Christ does these things in them.”