5. Libri duo de pœnitentia. These books on Penitence were written about a.d. 384, against the Novatians. In the first book the writer proves that the power of forgiving sins was left by Christ to His Church. In the second book, insisting on the necessity of repentance and confession, he also refutes the Novatian interpretations of Heb. vi. 4–6 and St. Matt. xii. 31–32. This treatise has also undeservedly been questioned on doctrinal grounds by some moderns.