For he that wrought effectually in Peter to the apostleship of the circumcision ( ὁ γὰρ ἐνεργήσας πέτρῳ εἰς ἀποστολὴν τῆς περιτομῆς); he that had wrought on Peter's behalf for apostleship of the circumcision.
In form, the sentence is an absolute statement of fact; but its bearing in the context would be fairly represented by rendering it relatively, "for that he who," etc.; for it was the perception of the fact here stated which led that assembly to the conviction that Paul had been entrusted with the apostleship of the uncircumcision.
The dative πέτρῳ can scarcely be governed, as the Authorized Version presupposes, by the preposition in ἐνεργήσας, this verb not being a separable compound; it is rather the dativus commodi, as in Proverbs 31:12, ἐνεργεῖ τῷ ἀνδρὶ εἰς ἀγαθά.
When operation in a subject is meant, the preposition ἐν is added, as Ephesians 1:20; Ephesians 2:2; Galatians 3:5. The worker is God, not Christ. God wrought on Peter's behalf for apostleship of the circumcision; that is, towards, in furtherance of, his work as their apostle, by constituting him their apostle, by making his ministry effectual in turning their hearts to Christ, and by miracles wrought by his hands, including the impartation through him of miraculous gifts to his converts; for such were "the signs of the apostle" (2 Corinthians 12:12).
The same was mighty in me toward the Gentiles ( ἐνήργησε καὶ ἐμοὶ εἰς τὰ ἔθνη); had wrought also on my behalf towards the Gentiles. Comp. Acts 15:12, "They hearkened unto Barnabas and Paul rehearsing what signs and wonders God had wrought ( ἐποίησεν) among the Gentiles by them;" where likewise, as here, the aorist tense is used of action they were then looking back upon as past.
The absence of Barnabas's name in this verse, though mentioned in the next, is significant. Barnabas was not an apostle in that highest sense of the term in which Paul was an apostle, and which alone he is now thinking of; although he was associated with Paul, both in ministerial work and in that lower form of apostleship which beth had received from men (comp.
Acts 14:4, Acts 14:14; and Dissertation I. in the Introduction).