Ver. 9. "At this time will I come, and Sarah shall have a son."

This promise then and word of God it was that fashioned Isaac, and begat him. For what if a womb was its instrument and the belly of a woman? Since it was not the power of the belly, but the might of the promise that begat the child. Thus are we also gendered by the words of God. Since in the pool of water it is the words of God which generate and fashion us. For it is by being baptized into the Name of the Father and of the Son and of the Holy Ghost that we are gendered. And this birth is not of nature, but of the promise of God. (John iii. 3; Eph. v. 26; James i. 18; 1 Pet. iii. 21.) For as after first foretelling the birth of Isaac, He then accomplished it; so ours also He had announced before, many ages ago by all the Prophets, and afterwards brought it to pass. You know how great He has set it forth as being, and how, as He promised a great thing, He furnished it with abundant ease! (Hos. ii. 1, etc.) But if the Jews were to say, that the words, "In Isaac shall thy seed be called," mean this, that those born of Isaac should be reckoned to him for a seed, then the Edomites too, and all those people, ought to be denominated his sons, since their forefather Esau was a son of his. But now so far are they from being called sons, that they are the greatest possible aliens. You see then that it is not the children of the flesh that are the children of God, but that even in nature itself the generation by means of baptism from above was sketched out beforehand. And if you tell me of the womb, I in return have to tell you of the water. But as in this case all is of the Spirit, so in the other all was of promise. For the womb was more chilled than any water owing to barrenness and to old age. Let us then gain accurate knowledge of our own nobility, and display a life worthy of it. For in it is nothing fleshly or earthy: hence neither let there be in us. For it was neither sleep, nor the will of the flesh (John i. 13), nor embraces, nor the madness of desire, but "God's love toward man," which wrought the whole. (Tit. iii. 5.) And as in that case it was when the age was past hope, so in this also it was when the old age of sins had come over us, that Isaac ¹ suddenly sprang up in youth, and we all became the children of God, and the seed of Abraham. (Is. xl. 31.)