The Apostle Paul
Galatians 2:8ESV·traditional attribution

(for he who worked through Peter for his apostolic ministry to the circumcised worked also through me for mine to the Gentiles),

John Calvin Reformed @genevareformer

8. He that wrought effectually. That the province which had been assigned to him was truly his own, is proved by the exertion of divine power during his ministry. Now, this manifestation of divine energy, as we have frequently seen, is the seal by which his doctrine was attested, and his office as a teacher sanctioned.

Matthew Henry Presbyterian @wholebiblehenry

It should seem, by the account Paul gives of himself in this chapter, that, from the very first preaching and planting of Christianity, there was a difference of apprehension between those Christians who had first been Jews and those who had first been Gentiles.

Commenting on Galatians 2:1-10

John Gill Reformed Baptist @doctorgill

For he that wrought effectually in Peter,.... The Syriac version renders it, "he who exhorted Peter to"; the Arabic version is, "he who strengthened Peter in"; the Spirit of God is meant, who filled Peter with such eminent gifts, and inspired him with so much zeal and resolution to the apostleship of circumcision, to discharge his office as an apostle among the Jews; and who...