11 “And let them who know Your Name, hope in You”, when they shall have ceased hoping in wealth, and in the other enticements of this world. For the soul indeed that seeks where to fix her hope, when she is torn away from this world, the knowledge of God's Name seasonably receives. For the mere Name of God has now been published everywhere: but the knowledge of the name is, when He is known whose name it is. For the name is not a name for its own sake, but for that which it signifies.
Now it has been said, “The Lord is His Name.” Wherefore whoso willingly submits himself to God as His servant, has known this name. “And let them who know Your Name hope in You”. Again, the Lord says to Moses, “I am That I am; and You shall say to the children of Israel, I Am, has sent me.” “Let them” then “who know Your Name, hope in You;” that they may not hope in those things which flow by in time's quick revolution, having nothing but “will be” and “has been.” For what in them is future, when it arrives, straightway becomes the past; it is awaited with eagerness, it is lost with pain.
But in the nature of God nothing will be, as if it were not yet; or has been, as if it were no longer: but there is only that which is, and this is eternity. Let them cease then to hope in and love things temporal, and let them apply themselves to hope eternal, who know His name who said, “I am That I am;” and of whom it was said, “I Am has sent me.” “For You have not forsaken them that seek You, O Lord.” Whoso seek Him, seek no more things transient and perishable; “For no man can serve two masters.”
Source: The Enarrations, or Expositions, on the Psalms (New Advent)