From Sovereign Grace's Bob Kauflin: "Because God’s saving acts in history and in our lives demand new songs. Because 1000 tongues or a 1000 songs will never be enough. Because Jesus Christ is a great Savior worthy of unending praise. Because the Word of God is eternal and life-changing. Because this is one small way we can contribute to building up the church, comforting God’s people, and advancing the gospel, all for the glory of God. And because, in the words of King David, “He put a new song in my mouth, a song of praise to our God. Many will see and fear, and put their trust in the LORD” (Ps. 40:3)."
I'd like to think of our songs as drops in a series of waves beating in endless succession against the shores of God's glory. Each generation is a new wave, made up of a lot from the old and a bit from the new.