The predecessor of Marcion,* he came to Rome from Syria, according to Epiphanius, about 137-41. Irenaeus continues that he publicly professed orthodoxy, but taught heresy in secret until he separated from the congregation. He taught that the OT God is known and righteous, while the Father of the Lord Jesus Christ is unknown and good. Later writers expand or contradict Irenaeus, making Cerdo a Docetic* believing in the resurrection of the soul and presaging the canon of Marcion.