Saint Crispus is one of the better-attested members of the Seventy, for he appears by name in the New Testament — in the Acts of the Apostles (18:8) and in Saint Paul's First Epistle to the Corinthians (1:14). He was a prominent Jewish leader at Corinth, the ruler (archisynagogos) of the synagogue, and so one of the most influential religious figures of the city; his position implies a thorough training in the Scriptures, the law, and the governance of the synagogue.
He enters the record during Paul's mission at Corinth, about AD 50–52. Paul preached first in the synagogue until opposition arose, and amid that controversy Crispus came to believe that Jesus is the Messiah: Acts records that he 'believed in the Lord with all his household.' The conversion of one of the city's leading Jewish authorities was a significant event for the Corinthian mission.
Paul himself baptized Crispus — a fact Paul recalls in 1 Corinthians while addressing divisions in the Church, noting that he had baptized few there in person. Because Paul usually left baptizing to his coworkers, his particular mention suggests the weight of Crispus's conversion.
Orthodox tradition numbers Crispus among the Seventy Apostles whom Christ sent out, and later ecclesiastical tradition records that he became Bishop of Aegina, an island in the Saronic Gulf near Athens, devoting himself to missionary preaching and the planting of Christian communities. The New Testament does not mention this episcopate, and accounts of his repose vary — some peaceful, some under persecution — but the Church honors him among the Seventy, both individually on January 4 and with the whole apostolic circle.