Musar sur Les Psaumes 71:23

And David when he had already reached this level a great measure said: "May my words be pleasing to Him; I shall rejoice in G-d" (Tehilim 104:34), and "I will come to the altar of God, to God my exceeding joy, and I will thank You with a lyre, O G-d, My G-d" (Tehilim 43:4). And he said: "My lips sing praises, when I sing to You, and my soul which You have redeemed" (Tehilim 71:23).