Whereunto I am ordained a preacher, and an apostle
He was ordained or appointed to be a preacher of the Gospel from all eternity, and was separated or set apart unto it in time, and was put into the ministry of it by Christ himself, and was not a common or ordinary preacher of the word, but an apostle, an extraordinary officer in the Gospel church.
I speak the truth in Christ, and lie not;
which are a sort of an oath, or an appeal to Christ the omniscient God, for the truth of what he said, concerning his ordination to the Gospel; see a like phrase in ( Romans 9:1 ) . The phrase, "in Christ", is left out in the Alexandrian copy, and in three of Beza's ancient copies, and in some others, and in the Vulgate Latin, Syriac, Arabic, and Ethiopic versions;
a teacher of the Gentiles in faith and verity;
the Gospel of the uncircumcision, or which was to be preached to the uncircumcised Gentiles, was committed to this apostle; and his work and ministry lay among them, and therefore he is called the apostle of the Gentiles: and so he was in faith and verity; which may regard the subject matter of his teachings and ministry; it was the faith and truth of the Gospel, even the whole of it, the faith which was once delivered to the saints, and the truth as it is in Jesus; or else the character of the apostle, as a teacher, that he was a true and faithful one, who with all integrity and veracity, fully and faithfully preached the Gospel; and since he was appointed a teacher of it to the Gentiles, this is another argument why they, as well as the Jews, should be prayed for.