showed ... to them of Damascus, and at Jerusalem - omitting Arabia; because, beginning with the Jews, his object was to mention first the places where his former hatred of the name of Christ was best known: the mention of the Gentiles, so unpalatable to his audience, is reserved to the last.
repent and return to God, and do works meet for repentance - a brief description of conversion and its proper fruits, suggested, probably, by the Baptist’s teaching (Luk 3:7, Luk 3:8).