St. Clement was one of the Seventy Apostles sent out two by two by the Lord Jesus Christ to preach and heal in His Name when He was still teaching and working miracles in Israel during His Ministry. They went and preached, and were received by some and rejected by others, as the Lord had told them. When a city rejected them, they were to “Go your ways out into the streets of the same, and say, ?Even the dust of your city which cleaveth unto us we do wipe off against you: notwithstanding be ye sure of this, that the Kingdom of God is come nigh unto you'” (Luke 10:10-11).
After Pentecost, St. Clement became the Bishop of Sardis (Serdica) in Lydia of Asia Minor, which was an important city at that time, and one of the cities named by St. John the Evangelist in Revelations that needed to repent (Rev. 3:1-6). St. Clement is also named by St. Paul (Phil. 4:3) as one of the fellow laborers in the Gospel, “whose names are in the book of life.” St. Clement is commemorated with all of the Seventy Apostles on January 4, with SS Apelles and Lucius on September 10, and with SS Nathaniel and Luke on April 22.