Galatians 1:9

We] the epistolary plural, as also in Galatians 1:8 on repetition it becomes the emphatic 'I.' Said before] in his personal teaching when with them. Now again] emphatic and solemn repetition.

11-17. The gospel which St. Paul preached not of human origin. Twofold proof of the fact: (1) the Apostle's whole course of life until his conversion was intensely Jewish, and only by a divine revelation was he made a messenger of Christ; and (2) after his conversion he remained aloof from the men from whom he might have been supposed to receive his message.

Paraphrase. '(11, 12) I solemnly assure you that the doctrine which I have taught was not a human product or derived from any human source, but that it came to me by revelation from Christ Himself. (13, 14) In proof of this, consider how unlikely it is that I, an intense Jewish zealot and a fierce persecutor of the Church, should have been transformed into a preacher of Christ by any merely human means. (15, 16) But when God, who had chosen me from my birth and graciously called me, disclosed Christ to my heart and designated me as His messenger, I did not resort to human authorities in order to learn what my message was to be; (17) I did not visit the primitive Apostles to learn anything from them, but went away into the seclusion of Arabia, and thence returned, not to Jerusalem, but to Damascus.'