Genesis 7:3

3. To keep seed alive upon the face of all the earth. That is, that hence offspring might be born. But this is referred to Noah; for although, properly speaking, God alone gives life, yet God here refers to those duties which he had enjoined upon his servant: and it is with respect to his appointed office, that God commands him to collect animals that he may keep seed alive. Nor is this extraordinary, seeing that the ministers of the gospel are said, in a sense, to confer spiritual life. In the clause which next follows, upon the face of all the earth, there is a twofold consolation: that the waters, after they had covered the earth for a time, would again cease, so that the dry surface of the earth should appear; and then, that not only should Noah himself survive, but, by the blessing of God, the number of animals should be so increased, as to spread far and wide through the whole world. Thus, in the midst of ruin, future restoration is promised to him. Moses is very earnest in showing that God took care, by every means, to retain Noah in obedience to his word, and that the holy man entirely acquiesced. This doctrine is very useful, especially when God either promises or threatens anything incredible, since men do not willingly receive what seems to them improbable. For nothing was less accordant with the judgment of the flesh, than that the world should be destroyed by its Creator; because this was to subvert the whole order of nature which he had established. Wherefore, unless Noah had been well admonished of this terrible judgment of God, he never would have ventured to believe it; lest he should conceive of God as acting in contradiction to himself. The word היקום (hayekom,) which Moses here uses has its origin from a word signifying to stand; but it properly means whatever lives and flourishes.