Apologeticae sive Theologiae Fundamentalis, Tomus I: Demonstratio Christiana

1. Notion. The arguments by which the fact — that is, the existence or the divine origin — of revelation is to be proved are called motives of credibility or criteria of revelation. They are called motives of credibility¹ with reference to the ultimate end, because by them the fact of revelation is rendered rationally certain, and from this certainty the individual revealed truths become evidently credible. They are called criteria of revelation with reference to the proximate end, because from them true revelation is recognized and distinguished from spurious revelation.

2. Qualities. In order, however, that the criteria may answer to their end, they must be certain and clear.

Certain, i. e. such as to convince every sound reason, excluding any prudent doubt concerning the divine origin of the proposed revelation. In the concrete, indeed, it is not required that each and every one of them be absolutely certain, because in view of the diversity of men a diverse, that is, a relative, certainty suffices. A child rationally assents to the simple authority of parents or teachers; the unlearned, to the testimony of trustworthy men; but the learned, and above all sceptics, are scarcely convinced even by the greatest reasons. Since, however, the criteria must be suited to all, it is necessary that at least all of them taken together possess not merely relative, but absolute certainty.²

Clear, i. e. such as can be grasped by every sound reason. Not, indeed, must all of them be of such great clarity that they are easily known by all men one and all, since the faculty of judgment varies with the variety of talent and learning. Nevertheless, let at least some criteria be of such a kind that any lover of truth can learn from them the existence of divine revelation.

The certainty of the criteria taken together must therefore be so great that it befits even the most learned absolutely; the clarity, on the other hand, so great that it lies open even to the most unlearned relatively. And the greater the certainty and clarity of the individual criteria, the more they have the nature and force of criteria.

3. Division. The criteria of revelation are divided according to the source from which they proceed and according to the end which they attain.

According to their source, the criteria are either internal (intrinsic) or external (extrinsic). The former are drawn from the philosophical character of the doctrine itself which is declared to be revealed; the latter consist in the historical facts which accompany the manifestation of the doctrine.

According to their end, each of the two is again either negative or positive. Negative are those which prove negatively, i. e. that nothing stands in the way of such a doctrine being revealed; positive, on the other hand, are those which prove positively, i. e. that such a doctrine has truly been revealed.