Paul arrives in Corinth, although there is opposition, many Corinthians - both Jews and Gentiles - believe and are baptized. In a vision God tells the apostle that he has "many in this city who are my people" and so Paul remains there for 18 months teaching the word of God, before returning to Antioch. Now as then God is sovereign in our desires to make Christ known and he will not let the word come back void.