It's entitled, "Meditation on Human Redemption" and comes from The Prayers and Meditations of Saint Anselm.
"I pray you, Lord,
make me taste by love what I taste by knowledge;
let me know by love what I know by understanding.
I owe you more than my whole self, but I have no more,
and by myself I cannot render the whole of it to you.
Draw me to you, Lord, in the fullness of love.
I am wholly yours by creation;
make me all yours, too, in love."