THESE two books were written against the Novatian heresy, which took its name, and to a considerable extent its form, from Novatus, a priest of the Church of Carthage, and Novatian, schismatically consecrated bishop at Rome. It was the outcome of a struggle which had long existed in the Church upon the question of the restitution to Church privileges of those who had fallen into grievous sin, and the possibility of their repentance. St. Ambrose, in writing against the Novatians, seems to have had some recent publication of theirs in his mind, which is now unknown. He begins by commending gentleness, a quality singularly wanting in the sect; speaks of the power committed to the Church of forgiving the greatest sins, and points out how God is more inclined to mercy than to severity, and refutes the arguments of the Novatians based on certain passages of Holy Scripture. In the second book, after urging the necessity of careful and speedy repentance, and the necessity of confessing one's sins, St. Ambrose meets the Novatian arguments based on Heb. vi. 4-6, from which they inferred the impossibility of restoration; and on St. Matt. xii. 31, 32, our Lord's words concerning sin against the Holy Spirit.