Tertullian also attacked the position that only one pared-down gospel was sacred. He proposed that Irenaeus’ list of gospels, the four we now have, were all sacred, and all taught about Christ. He also proposed that a number of works in addition to Paul’s epistles were sacred, such as 1 Clement, the Shepherd of Hermas, and others. Furthermore, he asserted that all Christian doctrine could be found in writing, and that none of it was to be “secret.”