6 Be therefore like Him in piety, and earnest in meditation: for “the invisible things of Him are clearly seen, being understood by the things that are made;” look upon the things that are made, admire them, seek their author. If you are unlike, you will turn back; if like, you will rejoice. And when, being like Him, you shall have begun to approach Him, and to feel God, the more love increases in you, since God is love, you will perceive somewhat which you were trying to say, and yet couldest not say.
Before you felt God, you thought that you could express God; you begin to feel Him, and then feelest that what thou dost feel you can not express. But when you have herein found that what thou dost feel cannot be expressed, will you be mute, will you not praise God? Will you then be silent in the praises of God, and will you not offer up thanksgivings unto Him who has willed to make Himself known unto you? Thou praised Him when you were seeking, will you be silent when you have found Him?
By no means; you will not be ungrateful. Honour is due to Him, reverence is due to Him, great praise is due to Him. Consider yourself, see what you are: earth and ashes; look who it is has deserved to see, and What; consider who you are, What to see, a man to see God! I recognise not the man's deserving, but the mercy of God. Praise therefore Him who has mercy....
Source: The Enarrations, or Expositions, on the Psalms (New Advent)