Acts 18:24-28

Meanwhile, there was a Jew named Apollos, a native of Alexandria, who came to Ephesus. He was a cultured and eloquent man, well versed and mighty in the Scriptures. He had been instructed in the way of the Lord, and burning with spiritual zeal, he spoke and taught diligently and accurately the things concerning Jesus, though he was acquainted only with the baptism of John. He began to speak freely (fearlessly and boldly) in the synagogue; but when Priscilla and Aquila heard him, they took him with them and expounded to him the way of God more definitely and accurately. And when [Apollos] wished to cross to Achaia (most of Greece), the brethren wrote to the disciples there, urging and encouraging them to accept and welcome him heartily. When he arrived, he proved a great help to those who through grace (God's unmerited favor and mercy) had believed (adhered to, trusted in, and relied on Christ as Lord and Savior). For with great power he refuted the Jews in public [discussions], showing and proving by the Scriptures that Jesus is the Christ (the Messiah).