The account given by Irenaeus of the doctrine of Cerdo is that he taught that the God preached by the law and the prophets was not the Father of Jesus Christ; for that the former was known, the latter unknown; the former was just, the latter good. The account given by Pseudo-Tertullian () may be regarded as representing that given in the earlier "Syntagma" of Hippolytus, which was also made use of by Philaster ("Haer". 44) and Epiphanius ("Haer". 41). It runs that Cerdo introduced two first principles ("archai") and two gods, the one good, the other evil, the latter of whom was the creator of the world. Here we are to note the important difference that to the good god is opposed in the account of Irenaeus a just one; in that of Hippolytus, an evil one. of Hippolytus, Cerdo is said to have taught three principles of the universe, ", dikaion, hylen".