Yet the number of the children of Israel will be as the sand of the sea, which can't be measured nor numbered; and it will come to pass that, in the place where it was said to them, 'You are not my people,' they will be called 'sons of the living God.'
The Prophet there designedly exposes to scorn the hypocrites, who falsely pleaded that prophecy, ‘Look on the stars of heaven, and on the sand of the sea, if thou can’t number them; so shall thy seed be.’ Since, then, Isaiah saw that hypocrites, relying on that prophecy, were rising so perversely against him, he said, “Be it so, be it so, that ye are as the stars of heaven, and as the sand of the sea; yet a remnant only shall be saved;” which means, “The Lord will at last cut you down, and reduce you to so small a number, that ye shall be extremely few.” Now, on the other hand, Hosea says, That after the Israelites shall be reduced to a very small number, that nothing but waste and solitude will appear, then the Lord will restore the Church beyond all human thoughts and will prove that he had not in vain promised to Abraham that his seed would be as the sand of the sea. Since, then, the Lord wonderfully defends his Church, and preserves it in this world, so that at one time he seems to bury it, and then he raises it from death; at one time he cuts it down as to its outward appearance, and then afterwards he renews it; we ought to take heed, lest we measure according to our own judgement and carnal reason, what the Lord declares respecting the preservation of his Church. For its safety is often hid from the eyes of men. However the case may be, God does not bind himself here to human means, nor to the order of nature, but his purpose is to surpass by his incredible power whatever the minds of men can conceive. 