John Calvin Commentary Galatians 1:16

"to reveal his Son in me, that I might preach him among the Gentiles; straightway I conferred not with flesh and blood:" — Galatians 1:16 (ASV)

To reveal his Son to me. If we read it as “to reveal by me,” it will express the purpose of the apostleship, which is to make Christ known. And how was this to be accomplished? By preaching him among the Gentiles, which the false apostles treated as a crime. But I consider the Greek phrase ἐν ἐμοί to be a Hebrew idiom for to me; for the Hebrew particle ב (beth) is frequently redundant, as all who know that language are well aware. The meaning will therefore be that Christ was revealed to Paul, not so that he alone might enjoy and silently keep to himself the knowledge of Christ, but so that he might preach among the Gentiles the Savior whom he had known.

Immediately I conferred not. To confer with flesh and blood means to consult with flesh and blood. Regarding the meaning of these words, his intention was absolutely to have nothing to do with any human advice. The general expression, as will soon become clear from the context, includes all people, and all the prudence or wisdom they may possess. He even makes a direct reference to the apostles for the express purpose of exhibiting, in a stronger light, God's direct calling. Relying on God's authority alone, and asking for nothing more, he proceeded to carry out the duty of preaching the gospel.