The Middle Ages, and in particular the twelfth century, with its monks who were philosophers, theologians, and mystics, hung upon biblical thought and through it did its thinking, its loving, and its acting. The Old and the New Testaments were studied and meditated upon together, though the Old Testament was more often commented upon than was the New. Both offered two successive stages, represented by the law and by grace. For the men of the twelfth century Holy Scripture was the basis of their symbolic mentality. Through Scripture they could distinguish a duality of meanings which can be stated precisely under the terms “letter” and “spirit.” This double terminology was comprehended on two different levels and depended on the degree of the individual's evolution. Saint Bernard understood it very well when he alluded to the ordinary mode of seeing and to the spiritual mode. The heart's vision sees in the mind (Sermon XLV, 5, on the Song of Songs. Just as that hearing which is not of the body but which belongs to the heart understands what the ears could not hear, there are, according to Saint Bernard, three kinds of language to which three modes of understanding correspond: the mode of the hireling, that of the son, and that of the wife (Sermon VII, 2, on the Song of Songs) ? The first stays on the threshold to knowledge, the second crosses it, but only the wife penetrates into true knowledge which designates a knowledge acquired more by intuition than by learning and which Saint Jerome called “scientia secretorum.” This stimulates another way of thinking and of loving and coincides with a new dimension of being. In regard to the comprehension of symbolic content, three steps or successive stages are involved here.