10 “So I will speak good of You in my life, and in Your name I will lift up my hands”. Now in my life which to me You have given, not in that which I have chosen after the world with the rest among many lives, but that which You have given to me through Your mercy, that I should praise You. “So I will speak good of You in my life.” What is “so”? That to Your mercy I may ascribe my life wherein You I praise, not to my merits. “And in Your name I will lift up my hands.” Lift up therefore hands in prayer. Our Lord has lifted up for us His hands on the Cross, and stretched out were His hands for us, and therefore were His hands stretched out on the Cross, in order that our hands might be stretched out unto good works: because His Cross has brought us mercy. Behold, He has lifted up hands, and has offered for us Himself a Sacrifice to God, and through that Sacrifice have been effaced all our sins. Let us also lift up our hands to God in prayer: and our hands being lifted up to God shall not be confounded, if they be exercised in good works. For what does he that lifts up hands? Whence has it been commanded that with hands lifted up we should pray to God? For the Apostle says, “Lifting up pure hands without anger and dissension.” It is in order that when you lift up hands to God, there may come into your mind your works. For whereas those hands are lifted up that you may obtain that which you will, those same hands you think in good works to exercise, that they may not blush to be lifted up to God. “In your name I will lift up my hands.” Those are our prayers in this Idumæa, in this desert, in the land without water and without way, where for us Christ is the Way, but not the way of this earth.
11....Already our fathers are dead, but God lives: here we could not always have fathers, but there we shall always have one living Father, when we have our father-land....What sort of country is that? But you love here riches. God Himself shall be to you your riches. But you love a good fountain. What is more passing clear than that wisdom? What more bright? Whatsoever is an object of love here, in place of all you shall have Him that has made all things, “as though with marrow and fatness my soul should be filled: and lips of exultation shall praise Your name.” In this desert, in Your name I will lift up my hands: let my soul be filled as though with marrow and fatness, “and my lips with exultation shall praise Your name.” For now is prayer, so long as there is thirst: when thirst shall have passed away, there passes away praying and there succeeds praising. “And lips of exultation shall praise Your name.”
Source: The Enarrations, or Expositions, on the Psalms (New Advent)