Acts 18:1
1-4. came to Corinth—rebuilt by Julius Cæsar on the isthmus between the Ægean and Ionian Seas; the capital of the Roman province of Achaia, and the residence of the proconsul; a large and populous mercantile city, and the center of commerce alike for East and West; having a considerable Jewish population, larger, probably, at this time than usual, owing to the banishment of the Jews from Rome by Claudius Cæsar (Ac 18:2). Such a city was a noble field for the Gospel, which, once established there, would naturally diffuse itself far and wide.
Acts 19:1
1-3. while Apollos was at Corinth—where his ministry was so powerful that a formidable party in the Church of that city gloried in his type of preaching in preference to Paul's (1Co 1:12; 3:4), no doubt from the marked infusion of Greek philosophic culture which distinguished it, and which the apostle studiously avoided (1Co 2:1-5).
Paul having passed through the upper coasts—"parts," the interior of Asia Minor, which, with reference to the seacoast, was elevated. came to Ephesus—thus fulfilling his promise (Ac 18:21). finding certain disciples—in the same stage of Christian knowledge as Apollos at first, newly arrived, probably, and having had no communication as yet with the church at Ephesus.