17 But if, while we seek to be justified by Christ, we ourselves also are found sinners, is Christ therefore a minister of sin? Certainly not!
18 For if I build again those things which I destroyed, I make myself a transgressor.
19 For I through the law died to the law that I might live to God.
But if (v.17) — Paul is stating that this is the case.
we (v.17) — Jews who failed to find righteousness by the law so turned to Christ to find it.
sinners (v.17) — those who have "missed the mark"
Jews used the term "sinners" to refer to Gentiles, but in light of the life and death of Christ, they are in the same situation (Romans 3:9).
minister (v.17) = one who renders service. Since Christ revealed that the Jews were also sinners, does He further the interests of sin, or extend the dominion of sin (personified)?
Certainly not! (v.17) — God forbid. Literally "let it not be."
If we Christians, who have regarded ourselves as justified by faith in Christ, now resort to legal methods, and Jewish rites and ceremonies, in order to be justified, is that not confessing that we are sinners and in need of being saved, and is not Christ then at fault for our present sinful state? Can this be possible? "Is Christ a minister of sin?"
Paul recoils from so monstrous a suggestion. "God forbid," he cries, using a phrase he commonly employed to express horror and deprecation.
The real "sinner," the actual transgressor, is the one who turns from Christ to the Law, who tries to add to justification by faith justification by works, who supplants Christ by supplementing Christ, and who offers self-righteousness in place of the righteousness of Christ. "For if I build up again those things which I destroyed, I prove myself a transgressor." Paul here courteously puts himself in the place of Peter or his companions in error. He supposes himself guilty of taking so false a step. If he should go back to law as a means of salvation, then he would convict himself of sin in ever having renounced the law; or if it has been right to renounce the law, then it is wrong to return now to the law. In either case he would be not vaguely a "sinner" in condition, but a real "transgressor" in action. — The Epistle of Paul to the Galatians, by Charles R. Erdman, page 53-54.
if I (v.18) — If Paul did what Peter and the Judaizers were, in fact, doing …
build again (v.18) — labor to build in a figurative sense
things (v.18) — the law as a means of justification
destroyed (v.18) — as in the demolition of a building
transgressor (v.18) = one who oversteps a prescribed limit. If Paul attempts again to gain righteousness by the law, the law will once again show that he falls short.
I (v.19) — Paul, or anyone else
died to the law (v.19) — The law condemned Paul and so separated him from any hope of gaining righteousness by it. Sin is the killer (Romans 7:11), but the law brings the knowledge of sin (Romans 3:20).
that I might live (v.19) — death was necessary for new life
live (v.19) — justified before God
The law makes us sinners and punishes us for being sinners.
Instead of finding in the law a way of salvation, by the very operation of the law Paul was led to abandon the law, that he might love and serve God. "For I through the law died unto the law, that I might live unto God." When Paul realized what the law really demanded, in all its deep meaning and implication, he discovered that he never could secure justification by his endeavor to keep the law. Rather the law passed on him a moral sentence of death. It revealed the reality and the depth of his sin; but it gave him no power to overcome sin. Therefore he turned from the law as a means of salvation, or of acceptance with God. He did so once for all, as truly as though he had died to the law. He could never return to it. He could never again look to it, as the Galatians were looking to it, as a ground of acceptance with God.
His relation to the law was broken as completely as earthly relations are broken by death. Yet his purpose was not that he might act in a way contrary to the law, but that he might truly, "live unto God," and attain that experience of holiness he had sought for in vain under the yoke of the law. — The Epistle of Paul to the Galatians, by Charles R. Erdman, page 54-55.
Faith in Christ was the means whereby Paul's complete and irreparable break with the law was effected. The Lord Jesus lived under the law, fully obeyed that law, assumed the guilt and penalty which the human race incurred by having violated the law, and in dying under the law satisfied its requirements. Thus He passed out of the realm where law in its legalistic aspect had control over Him. All believers were identified with Christ in His death and also in His resurrection, and thus have passed out of the realm of divine law so far as its legalistic aspect is concerned. — Galatians in the Greek New Testament, by Kenneth S. Wuest, page 80-81.