Acts 18:4

And he reasoned, &c.— Philo informs us, that many Jews inhabited Corinth, and the chief and best parts of Peloponnesus. And St. Luke in this place, as well as St. Paul in his two epistles to the Corinthians, has given plain intimation that there were several Jews in that city; for they had a synagogue there, into which the apostle went, as usual, every sabbath-day, and there he discoursed concerning the Christian doctrine, and laboured to convince— επειθε — both the Jews and devout Gentiles that it was true, and infinitely worthy of their regard. Among them was Epenetus, who was the first convert in Achaia, Romans 16:5 as the household of Stephanus was the first family converted there. The whole family of Stephanus was baptized by the apostle himself, and he also afterwards baptized Crispus and Caius; but he himself baptized no other of the Corinthians; he left that to his assistants, or to some of the first converts of the place; for the business of an apostle was not to baptize, but to preach the gospel, 1 Corinthians 14:17 and to plant churches.