V. 6-10. _Therefore it is contained in Scripture, Behold I lay in Zion an elect precious corner stone, and whoever believeth on Him shall not be put to shame. To you therefore who believe, He is precious, but to the unbelieving, the stone which the builders rejected is made a corner stone, and a stone of stumbling and a rock of offence, even to those that stumble at the word and believe not thereon, whereunto they were appointed. But ye are the chosen generation, the royal priesthood, the holy nation, the peculiar people, that ye should show forth the praise of him who has called you out of darkness into his wonderful light: who once were not a people, but are now the people of God, to whom God did not show mercy, but (now have obtained mercy) to whom He is now merciful._ I have before said, that St. Peter has enriched and fortified his Epistle well with Scripture, just as all preachers should do, in order that their foundation may rest entirely on the word of God. Here also he introduces four or five texts, one upon another. The first he has taken from the prophet Isaiah, word for word, that Christ is a precious corner stone or foundation, and is the very passage which we have just treated of and somewhat explained. It is truly an eminent proof text of the doctrine of faith, which is to be laid down as a foundation when we are to preach in a place where Christ has not been preached before. For it must be confessed that Christ is the stone on which faith should be built and should stand. But that the prophet does not speak in this place of a material stone is evident from this, that it afterward follows, "whoever believes on Him shall not be made ashamed." If I am to _believe_ on Him, it must be a stone in a spiritual sense. For how am I to believe on stone and wood? Besides, He must be truly God, since, in the first commandment, God has forbidden that we should believe on anything else, but on Him only. Since then this stone is laid as a foundation on which we are to trust, it must be God Himself. On the other hand, He cannot be God alone, but must also therewith be like man, because He must be a part of the building, and not merely a part, but the head. If a man then erects a building, one stone must be like the other, that each have the complexion, nature, and form of the other: therefore, since we are built on Christ, he also must be like us, and of the same nature with the other stones that rest upon Him, even a real humanity as we all have. Thus does the Scripture, by simple and few words, express so great a matter, even the entire _summa_ of our faith, and in such brief words comprises more than any man can express.