XXVII. (1.166) There are then a countless number of things well worthy of being displayed and demonstrated; and among them one which was mentioned a little while ago; for the oracles calls the person who was really his grandfather, the father of the practiser of virtue, and to him who as really his father, it has not given any such title; for the scriptures says, “I am the Lord God of Abraham thy father,” but in reality Abraham was his grandfather; and then proceeds, “And the God of Isaac,” and in this case he does not add, “thy father:” (1.167) is it not then worth while to examine into the cause of this difference? Undoubtedly it is; let us then in a careful manner apply ourselves to the consideration of the cause. Philosophers say that virtue exists among men, either by nature, or by practice, or by learning. On which account the sacred scriptures represent the three founders of the nation of the Israelites as wise men; not indeed originally endowed with the same kind of wisdom, but arriving rapidly at the same end. (1.168) For the eldest of them, Abraham, had instruction for his guide in the road which conducted him to virtue; as we shall show in another treatise to the best of our power. And Isaac, who is the middle one of the three, had a self-taught and self-instructed nature. And Jacob, the third, arrived at this point by industry and practice, in accordance with which were his labours of wrestling and contention. (1.169) Since then there are thus three different manners by which wisdom exists among men, it happens that the two extremes are the most nearly and frequently united. For the virtue which is acquired by practice, is the offspring of that which is derived from learning. But that which is implanted by nature is indeed akin to the others, for it is set below them, as the root for them all. But it has obtained its prize without any rivalry or difficulty. (1.170) So that it is thus very natural for Abraham, as one who had been improved by instruction, to be called the father of Jacob, who arrived at his height of virtue by practice. By which expression is indicated that not so much the relationship of one man to the other, but that the power which is fond of hearing is very ready for learning; the power which is devoted to practice being also well suited for wrestling. (1.171) If, however, this practiser of virtue runs on vigorously towards the end and learns to see clearly what he previously only dreamed of in an indistinct way, being altered and re-stamped with a better character, and being called Israel, that is, “the man who sees God,” instead of Jacob, that is, “the supplanter,” he then is no longer set down as the son of Abraham, as his father, of him who derived wisdom from instruction, but as the son of Israel, who was born excellent by nature. (1.172) These statements are not fables of my own invention, but are the oracle written on the sacred pillars. For, says the scripture: “Israel having departed, he and all that he had came to the well of the oath, and there he sacrificed a sacrifice to the God of his father Isaac.”{41}{#ge 46:1.} Do you not now perceive that this present assertion has reference not to the relationship between mortal men, but, as was said before, to the nature of things? For look at what is before us. At one time, Jacob is spoken of as the son of his father Abraham, and at another time he is called Israel, the son of Isaac, on account of the reason which we have thus accurately investigated.