J. Gresham Machen, in his Notes on Galatians, draws out a careful application of the principle argument of Galatians to the church today when he wrote:
The particular form of merit which they induced men to seek was the mertit of keeping the Law of Moses, particularly the cermonial law. At first sight, that fact might seem to destroy the usefulness of the epistle for the present day; for we of today are in no danger in desiring to keep Jewish fasts and feasts. But a little consideration will show that that is not at all the case. The really essential thing about the Judaizers’ contention was not found in those particular “works of the law” that they urged upon the Galatians as being one of the grounds of salvation, but in the fact that the urged any works at all. The really serious error into which they fell was not that they carried the ceremonial law over into the new dispensation, whither God did not intend it to be carried, but that they preached a religion of human merit as over against a religion of divine grace.
So the error of the Judaizers is a very modern error indeed, as well as a very ancient error. It is found in the modern church wherever men seek salvation by “surrender” instead of by faith, or by their own character instead of by the imputed righteousness of Christ, or by “making Christ master in the life” instead of by trusting in His redeeming blood. In particular, it is found wherever men say that “the real essentials” of Christianity are love, justice, mercy, and other virtues, as contrasted with the great doctrines of God’s word. These are all just different ways of exalting the merit of man over against the cross of Christ; they are all of them attacks upon the very heart and core of the Christian religion. And, against all of them the mighty polemic of this epistle to the Galatians is turned.