5 But let the following words remove all doubt that we ought not to understand carnally the words, “Whose partaking is in the same.”...What means, “the same”? What is ever in the same state; not what is now in one state, now in another. What then is, “the same,” save that which is? What is that which is? That which is everlasting...Behold “The Same: I Am that I Am, I AM.” You can not understand; it is much to understand, it is much to apprehend. Remember what He, whom you can not comprehend, became for you. Remember the flesh of Christ, towards which you were raised when sick, and when left half dead from the wounds of robbers, that you might be brought to the Inn, and there might be cured. Let us therefore run unto the Lord's house, and reach the city where our feet may stand; the city “that is building as a city: whose partaking is in The Same.”...
Source: The Enarrations, or Expositions, on the Psalms (New Advent)