Do we have in the Supper simply the testimony of the things already mentioned, or are they truly given to us in it?

See that Jesus Christ is the Truth, there can be no doubt that the promises which He made at the Supper, are actually fulfilled in it, and that what He figures in it is made true. Thus in accordance with what He promises and represents in the sacrament, I do not doubt that He makes us partakers of His very substance, in order to unite us with Himself in one life.