Acts 18:24

Now a certain Jew named Apollos, an Alexandrian by race, an eloquent man, came to Ephesus; and he was mighty in the Scriptures. This man had been instructed in the way of the Lord; and being fervent in spirit, he spake and taught accurately the things concerning Jesus, knowing only the baptism of John.

Although his information regarding the gospel was incomplete, he knew enough to proclaim the kingdom of God which John had declared to be "at hand," and to command people to be baptized unto the remission of sins, as John had done, declaring at the same time, of course, the Lordship of Jesus Christ.

He was a man of eloquence, learning, and great ability. No higher compliment can be paid than the one Luke gave, namely that he was mighty in the scriptures. As appears a little later, he baptized many.