The Apostle Paul
Galatians 2:14ASV·traditional attribution

But when I saw that they walked not uprightly according to the truth of the gospel, I said unto Cephas before them all, If thou, being a Jew, livest as do the Gentiles, and not as do the Jews, how compellest thou the Gentiles to live as do the Jews?

John Gill Reformed Baptist

But when I saw that they walked not uprightly,.... Or "did not foot it aright"; or "walked not with a right foot": they halted, as the Jews of old did, between two opinions, being partly for God, and partly for Baal; so these seemed, according to their conduct, to be partly for grace, and partly for the works of the law; they seemed to be...

John Calvin Reformed

14. But when I saw that they walked not uprightly. Some apply these words to the Gentiles, who, perplexed by Peter’s example, were beginning to give way; but it is more natural to understand them as referring to Peter and Barnabas, and their followers.

Jamieson-Fausset-Brown Reformed

walked not uprightly--literally, "straight": "were not walking with straightforward steps." Compare Gal 6:16. truth of the gospel--which teaches that justification by legal works and observances is inconsistent with redemption by Christ. Paul alone here maintained the truth against Judaism, as afterwards against heathenism (Ti2 4:16-17). Peter--"Cephas" in the oldest manuscripts before . . . all-- (Ti1 5:20).