Wikipedia
Stephanas (, Stephanas, , "crown" or "crowned") a member of the church at Corinth, whose family were among those the apostle had baptized (1 Cor. 1:16; 16:15, 17) as the “first-fruits of Achaia”.
He is mentioned by St. Paul in I Corinthians 16:17: "I was glad when Stephanas, Fortunatus and Achaicus arrived, because they have supplied what was lacking from you." and therefore Paul urged the church in Corinth to "be in subjection to such men and to everyone who helps in the work and labours" and to "acknowledge such men".
He has been supposed by some to have been the repentant “jailer of Philippi” (comp. Acts 16:33). The First Epistle to the Corinthians was written from Ephesus some six years after the jailer’s conversion, and he was with the apostle there at that time.