Whoever takes up any novelty outside the Scriptures, which might lead people to heresy, shall be sent away. But if he repents, he shall publicly condemn his own opinion and convert to the faith those whom he has decieved. (from the Penitential of Cummean)
The early Irish Christian writer Cummean (d. 662) was a renowned Biblical scholar. His influences were Augustine, Gregory the Great, Origen, Jerome, Cyprian and others. He valued the role of the Scriptures in the life of the Church. According to Cummean the teacher of the Scriptures must not just be a gifted orator but more importantly he must be accountable for what he teaches. If he has erred in his handling of Scripture he must show a sincere penitence and publically retract his comments. Anything less is pride and blasphemy.