John Calvin Commentary Galatians 3:4

"Did ye suffer so many things in vain? if it be indeed in vain." — Galatians 3:4 (ASV)

Have ye suffered so many things? This is another argument.

Having suffered so many things on behalf of the gospel, would they now, in an instant, lose it all? Indeed, he puts it as a reproach to them, should they be willing to lose the advantage of so many illustrious struggles which they had made for the faith. If the true faith had not been delivered to them by Paul, it was rash to suffer anything in defense of a bad cause; but they had experienced the presence of God amidst their persecutions. Accordingly, he charges the false apostles with ill-will in depriving the Galatians of such valuable ornaments.

But to mitigate the severity of this complaint, he adds, if it be yet in vain; thus inspiring them with the expectation of something better, and rousing them to the exercise of repentance. For the intention of all chastisement is, not to drive men to despair, but to lead them to a better course.