For the Galatian readers, as for Paul, there could be but _one gospel_. By his voice the call of God had reached their hearts, (ver. 6; ch. v. 8). The witness of the Spirit of God and of Christ in the supernatural gifts they had received, and in the manifold fruit of a regenerate life (ch. iii. 2-5; v. 22, 23), was evidence to them that the Apostle's message was "the true gospel of the grace of God." This they had gratefully acknowledged at the time of his first visit (ch. iv. 15). The proclamation of the crucified and risen Christ had brought to them unspeakable blessing. Through it they received the knowledge of God; they were made consciously sons of God, heirs of life eternal (ch. iii. 26; iv. 6-9; vi. 8). To entertain any other gospel, after this experience and all these professions, was an act of apostasy. "Ye are deserting (like runaway soldiers), _turning renegades_ from God:" such is the language in which Paul taxes his readers. In listening to the persuasion of the Judaists, they were "disobeying the truth" (ch. v. 7, 8). They were disloyal to conscience; they were trifling with the most sacred convictions of their lives, and with the testimony of the Spirit of God. They were forgetting the cross of Christ, and making His death of none effect. Surely they must have been "bewitched" to act thus; some deadly spell was upon them, which had laid memory and conscience both to sleep (ch. ii. 21-iii. 3).
The nature and the contents of the two "gospels" current in Galatia will be made clear in the further course of the Epistle. They were the gospels of Grace and of Law respectively; of Salvation by Faith, and by Works; of life in the Spirit, and in the Flesh; of the Cross and the Resurrection on the one hand, and of Circumcision and the Kalendar and "Clean meats" on the other; the gospels of inwardness, and of externalism--of Christ, and of self. The conflict between these two was the great struggle of Paul's life. His success was, historically speaking, the salvation of Christianity.
But this contention did not end with his victory. The Judaistic perversion appealed to tendencies too persistent in our nature to be crushed at one blow. The gospel of externalism is dear to the human heart. It may take the form of culture and moralities; or of "services" and sacraments and churchly order; or of orthodoxy and philanthropy. These and such things make themselves our idols; and trust in them takes the place of Faith in the living Christ. It is not enough that the eyes of our heart should once have seen the Lord, that we should in other days have experienced "the renewing of the Holy Ghost." It is possible to forget, possible to "remove from Him that called us in the grace of Christ." With little change in the form of our religious life, its inward reality of joy in God, of conscious sonship, of fellowship in the Spirit, may be utterly departed. The gospel of formalism will spring up and flourish on the most evangelical soil, and in the most strictly Pauline Churches. Let it be banned and barred out never so completely, it knows how to find entrance, under the simplest modes of worship and the soundest doctrine. The serried defence of Articles and Confessions constructed against it will not prevent its entrance, and may even prove its cover and intrenchment. Nothing avails, as the Apostle says, but a constant "new creation." The life of God in human souls is sustained by the energy of His Spirit, perpetually renewed, ever proceeding from the Father and the Son. "The life that I live in the flesh, I live by the Faith of the Son of God, who loved me and gave Himself for me." This is the true orthodoxy. The vitality of his personal faith in Christ kept Paul safe from error, faithful in will and intellect to the _one gospel_.