XVIII. (1.173) Having then said: "I am the Lord God of Abraham, the father and the God of Isaac," he adds: "Be not afraid," very consistently. For how can we any longer be afraid when we have thee, O God, as our armour and defender? Thee, the deliverer from fear and from every painful feeling? Thee, who hast also fashioned the archetypal forms of our instruction while they were still indistinct, so as to make them visible, teaching Abraham wisdom, and begetting Isaac, who was wise from his birth. For you condescended to be called the guide of the one and the father of the other, assigning to the one the rank of pupil, and to the other that of a son. (1.174) For this reason, too, God promised that he would not give him the land. I mean by the land here, all-prolific virtue, on which the practiser rests from his contests and sleeps, from the fact of the life according to the outward sense being lulled asleep, and that of the soul being awakened. Receiving gladly peaceful repose there, which he did not obtain without war, and the afflictions which arise from war, not by means of bearing arms and slaying men; away with any such notion! but by overthrowing the array of vices and passions which are the adversaries of virtue. (1.175) But the race of wisdom is likened to the sand of the sea, by reason of its boundless numbers, and because also the sand, like a fringe, checks the incursions of the sea; as the reasonings of instruction beat back the violence of wickedness and iniquity. And these reasonings, in accordance with the divine promises, are extended to the very extremities of the universe. And they show that he who is possessed of them is the inheritor of all the parts of the world, penetrating everywhere, to the east, and to the west, to the south, and to the north. For it is said in the scripture: "He shall be extended towards the sea, and towards the south, and towards the north, and towards the East."[genesis 28:14.] (1.176) But the wise and virtuous man is not only a blessing to himself, but he is also a common good to all men, diffusing advantages over all from his own ready store. For as the sun is the light of all those beings who have eyes, so also is the wise man light to all those who partake of a rational nature.