Crispus was the synagogue ruler in Corinth.
He believed in Jesus with his family after hearing Paul's preaching.
Acts 18:8Crispus, the synagogue ruler, and his entire household believed in the Lord; and many of the people of Corinth who heard Paul believed and were baptized.
He was one of only two people Paul baptized.
1 Corinthians 1:14I thank God that I did not baptize any of you except Crispus and Gaius,