Beware of dogs,.... By whom are meant the "judaizing" teachers, who were for imposing the works and ceremonies of the law upon the Gentiles, as necessary to salvation; and they have the name retorted on them they used to give to the Gentiles; see Mt 15:26; nor should they think it too severe, since the Jews themselves say ,"the face of that generation (in which the Messiah shall come) shall he, blkh ynpk, "as the face of a dog".'
'The apostle calls them so, because they returned to Judaism, as the dog to its vomit, 2Pe 2:22; and because of the uncleanness in which many of them lived, and the impudence they were guilty of in transforming themselves into the apostles of Christ, and putting themselves upon an equal foot with them; as also for their calumny and detraction, their wrangling with the apostles, snarling at their doctrines, and biting them with the devouring words of reproach and scandal: likewise, they may be styled dogs for their covetousness, being such greedy ones as in Isa 56:10, with feigned words making merchandise of men; and for their love of their, bellies, which they served, and not Christ, and made a god of, Php 3:19.
Moreover, because they were without, as dogs are, Re 22:15; having gone out from the communion of the saints, because they were not of them; or if among them, yet not true members of Christ, nor of his mystical body; all which are so many arguments why the saints should beware of them, and why their persons, conversation, and doctrine should be avoided.
Beware of evil workers: meaning the same persons, who were deceitful workers, did the work of the Lord unfaithfully, walked in craftiness, and handled the word of God deceitfully, endeavoured to subvert the Gospel of Christ, and the faith of men in it; who worked from bad principles, and with evil views; and notwithstanding their large pretensions to good works, teaching that justification and salvation were by them, which notion the apostle tacitly refers to in this character; yet were of bad a character, and such as Christ will reject another day as workers of iniquity; a character they deservedly bear, if there was no other reason for it than their preaching the doctrine of salvation by men's own works of righteousness, and who, and their ministry, are by all means to be shunned.
Beware of the concision; the men of the circumcision, as the Arabic version renders it; they chose to be called so, but the apostle would not give them that name, but calls them the "concision"; or "the concision of the flesh", as the Syriac version renders it; referring either to the cuttings in the flesh, forbidden Le 21:5; or to the circumcision of the flesh rather, which they valued themselves upon, and were for introducing among the Gentiles, whereby they made sad divisions, and cutting work among the churches; and were some of them at least "cut" off, as the Ethiopic version renders it, from the churches; and who, as much as in them lay, cut themselves off from Christ, and rendered him unprofitable to them; see Ga 5:2.
Misn. Sota, c. 9. sect.