"O sing to the Lord a new song," the psalmist cries; "sing to the Lord, all the earth" (Psalm 96:1). We moderns and postmoderns, committed as we are to the idea that whatever is most recent is best, are likely to think that the psalmist's call for "a new song" is a quest for novelty. I'm sure it's far more than that. His thinking, rather, is akin to the eighteenth-century hymnist and preacher Charles Wesley when he cried, "O for a thousand tongues to sing my great Redeemer's praise…!" Wesley wrote those words on the first anniversary of his transforming religious experience. Recalling all the wonders of God's work in his life, Wesley found one tongue, yes even a choir, inadequate. Such is the mood of the psalmist. All his vocabulary seems stunted and insufficient for the wonder he feels, so he yearns for a new way to declare the glory of God. He wants much more than new words, a fresh melody, or a different set of musical instruments; the poet wants a newness within his own person.
-- J. Ellsworth Kalas in Longing
to Pray: How the Psalms Teach Us to Talk with God