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.

Now what this that builds us up is, I have already said--namely,
faith, whereby we are laid on Christ, and repose our trust upon this
stone, and thus become like Him; and then this also must follow, that
the building must be fitted one part to the other, for the other
stones must all be laid and placed upon this stone. That is, of
course, that love is a fruit of faith.

But why does the prophet call Him a foundation stone? For this
reason: that no man can build a house except he lay one stone first
as a foundation, for the other stones in the building cannot stand
except on the foundation stone.

So we must all of us rest on Christ, and confess Him for a foundation
stone. Therefore we are not to pride ourselves that the stone must
receive something from us, but we must receive blessing from it
alone; for we do not bear it up, but it bears us up, and upon Him
lies sin, death, hell, a