Written by Paul, as the style proves. The heading and allusions to the apostle of the Gentiles in the first person throughout confirm his authorship (Gal 1:1; Gal 1:13-24; Gal 2:1-14). Irenaeus (Adv. Haer., 3:7, sec. 2, referring to Gal 3:19), Polycarp (Philippians 3, quoting Gal 4:26; Gal 6:7), Justin Martyr (Orat. ad Graecos, alluding to Gal 4:12; Gal 5:20), Tertullian (De Praescr., 60), uphold his authorship. The character of the Gallic Celts given by Caesar (B. G., Gal 4:5) accords with that described in this epistle: "the infirmity of the Gauls is, they are fickle in their resolves, fond of change, and not to be trusted." So Thierry: "flank, impetuous, impressible, eminently intelligent, but extremely inconstant, fond of show, perpetually quarreling, the fruit of excessive vanity." This description is not altogether inapplicable to their descendants in France and Ireland.

They received Paul at first with all affection, but soon wavered in their allegiance to the gospel, and hearkened as eagerly to Judaizing teachers as they had before to him (Gal 4:14-16). Many Jews resided in Ancyra (Josephus, Ant. 16:62); among these probably, as elsewhere, he began his ministry, and from them perhaps emanated the Judaizers who almost induced the Gentile Christians (Gal 4:8-9), who constituted the majority of the Galatian church, to undergo circumcision (Gal 1:6; Gal 3:1; Gal 3:3; Gal 5:2-3; Gal 6:12-13). Accustomed, when pagan, to the mystic worship of Cybele prevalent in the neighboring Phrygia, they the more readily were led to believe that the full privileges of Christianity could only be attained by submitting to elaborate ceremonial symbolism (Gal 4:9-11; Gal 5:7-12).

They even gave ear to the insinuation that Paul himself observed the law among the Jews though he persuaded the Gentiles to renounce it, and that he wished to keep his converts in a lower state of privileges, excluded from the high Christian standing enjoyed by the circumcised (Gal 4:16; Gal 5:11; compare Gal 2:17), and that in "becoming all things to all men" he was but a men-pleaser, seeking to form a party for himself; moreover that he was not, as he represented, an apostle divinely commissioned by Christ, but a mere messenger of the twelve and the Jerusalem church, and that his teaching now did not accord with that of Peter and James, the acknowledged "pillars" of the church, and ought therefore to be rejected. This design in writing then was:

(1) To maintain his apostolic authority (Gal 1:11-19; Gal 2:1-14.

(2) To counteract the Judaizers (Galatians 3-4), and to show that their teaching undermined Christianity itself by lowering its spirituality to external ceremonialism.

(3) To strengthen Galatian believers in faith toward Christ and in the fruit of the Spirit (Galatians 5-6); already he had testified against the Judaizers to their face (Gal 1:9; Gal 4:16; Act 18:28), and now that he has heard of the increase of the evil he writes to cheek it, "with his own hand" (Gal 6:11), a labor which he usually committed to an amanuensis. His sketch of his apostolic call and course confirms the history in Acts, and proves his independence of human authority however exalted. His protest against Peter's Judaizing dissimulation disproves the pope's, and even Peter's, supremacy, and shows that Peter, except when especially inspired, was fallible as other men (Gal 2:14-21). There is much in common between this epistle and that to the Romans; but the epistle to the Romans discusses justification by faith only, not by the law, in a didactic, logical mode; the epistle to the Galatians controversially, and with special reference to the Judaizers.

The style combines sternness (Galatians 1; Gal 3:1-5) with tenderness (Gal 4:19-20), betraying his strong emotions, and well adapted to move an impressible people such as the Galatians. He begins abruptly, as is suitable to the urgency of the subject and the seriousness of the evil. A tone of sadness too appears, such as is natural in an affectionate teacher who has just learned that his loved disciples are abandoning his teachings for those of others who pervert the truth and calumniate himself. The time of writing was after the visit to Jerusalem recorded in Act 15:1 (i.e. A.D. 50), if that visit be identical, as is probable, with that in Gal 2:1. Moreover, as allusion seems to be made to his seceded visit to the Galatians (in autumn A.D. 54) in Gal 1:9, "as we said before," and Gal 4:16, "have I become your enemy?" the epistle must have been later than A.D. 54.

Act 18:23 implies that at his second visit the Galatians were well established in the faith, which made their speedy declension the stranger. Gal 4:13, "ye know how I preached at the first" (Greek at rite former time), implies that Paul at the time of writing had been twice in Galatia; and Gal 1:6, "I marvel that ye are so soon removed," implies that he wrote not long after having left Galatia the second time, possibly (Alford) soon after he began his residence at Ephesus (Act 18:23; Act 19:1), which lasted from autumn A.D. 54 to Pentecost A.D. 57. However, the resemblance of this epistle to the epistle to the Romans favors the view (Conybeare and Howson) that it was not written until his stay at Corinth (Act 20:2-3, during the winter of A.D. 57-58), from whence he wrote the epistle to the Romans.

It seems unlikely that 1 and 2 Corinthians, so dissimilar, should intervene between those so much alike as Galatians and Romans, or that Galatians should intervene between 2 Thessalonians and 1 Corinthians. Even three years would be "soon" for their apostasy, they having betrayed no symptoms at his second visit (Act 18:23). A sudden exigency (tidings of Galatian Judaizing having reached him at Corinth from Ephesus) apparently called forth this epistle, for it maintains Christian liberty from carnal ceremonialism, and justification by faith only, in an admonitory and controversial tone.

That to Romans written subsequently, more systematically and deliberately sets forth the same truths for a church which as yet he did not personally know. The manner suits his relations to the two churches respectively; in writing to the Galatian church, which he had founded, he rests upon his authority; to the Roman church, whom he did not know personally, wholly upon argument: an undesigned coincidence and propriety confirming the authenticity. Reproof in Galatians predominates over praise and thanksgiving. Division. There are two controversial parts and a closing hortatory one.

I. He defends (Galatians 1-2) his apostolic authority and independence of the twelve.

II. He polemically by argument (Galatians 3), appeal (Gal 4:12-20), and allegorical illustration (Gal 4:1-7; Gal 4:21-30), maintains justification by faith and not by the deeds of the law.