In the early years of Christianity, the Church Fathers commented extensively on numerology. The Fathers repeatedly condemned the magical use of numbers which had descended from Babylonian sources to the Pythagoreans and Gnostics of their times. They denounced any system of philosophy which rested upon an exclusively numerical basis. Even so, they almost unanimously regarded the numbers of Holy Writ as full of mystical meaning, and they considered the interpretation of these mystical meanings as an important branch of exegesis. There was reluctance in the Christian teachers of the early centuries to push this recognition of the significance of numbers to extremes.