1. Enough, probably, has been done in our other books 47 in the way of answering the ignorant and profane attacks which the Manichæans make on the law, which is called the Old Testament, in a spirit of vainglorious boasting, and with the approval of the uninstructed. Here, too, I may shortly touch upon the subject. For every one with average intelligence can easily see that the explanation of the Scriptures should be sought for from those who are the professed teachers of the Scriptures; and that it may happen, and indeed always happens, that many things seem absurd to the ignorant, which, when they are explained by the learned, appear all the more excellent, and are received in the explanation with the greater pleasure on account of the obstructions which made it difficult to reach the meaning. This commonly happens as regards the holy books of the Old Testament, if only the man who meets with difficulties applies to a pious teacher, and not to a profane critic, and if he begins his inquiries from a desire to find truth, and not in rash opposition. And should the inquirer meet with some, whether bishops or presbyters, or any officials or ministers of the Catholic Church, who either avoid in all cases opening up mysteries, or, content with simple faith, have no desire for more recondite knowledge, he must not despair of finding the knowledge of the truth in a case where neither are all able to teach to whom the inquiry is addressed, nor are all inquirers worthy of learning the truth. Diligence and piety are both necessary: on the one hand, we must have knowledge to find truth, and, on the other hand, we must deserve to get the knowledge.
2. But as the Manichæans have two tricks for catching the unwary, so as to make them take them as teachers,—one, that of finding fault with the Scriptures, which they either misunderstand or wish to be misunderstood, the other, that of making a show of chastity and of notable abstinence,—this book shall p. 42 contain our doctrine of life and morals according to Catholic teaching, and will perhaps make it appear how easy it is to pretend to virtue, and how difficult to possess virtue. I will refrain, if I can, from attacking their weak points, which I know well, with the violence with which they attack what they know nothing of; for I wish them, if possible, to be cured rather than conquered. And I will quote such testimonies from the Scriptures as they are bound to believe, for they shall be from the New Testament; and even from this I will take none of the passages which the Manichæans when hard pressed are accustomed to call spurious, but passages which they are obliged to acknowledge and approve. And for every testimony from apostolic teaching I will bring a similar statement from the Old Testament, that if they ever become willing to wake up from their persistent dreams, and to rise towards the light of Christian faith, they may discover both how far from being Christian is the life which they profess, and how truly Christian is the Scripture which they cavil at.