Some songs are sung for God's glory. Some are sung to deny and defy His glory. And many are sung with no regard to Him at all.
"Sing praises to God, sing praises: sing praises unto our King, sing praises" (Psalm 47:6).
Of the innumerable things in creation that resound with the glory of its Creator, none more vividly proclaim His handiwork than the existence of music. I cannot fathom anyone who truly appreciates melody, harmony, rhythm, tempo, lyric, and the beauty they together express believing that music is the product of mindless evolution and the human brain.
Imagine a world without music. It would be like a world without color, flavor, fragrance, and touch. God could have formed such an existence for the human race created in His image. But then again, perhaps He could not have. Music is clearly an expression of some eternal beauty within our Maker's heart that had to come forth in the humanity created to most vividly reveal who He is. When we hear music, even if the singers and players deny or ignore the Giver of such a gift (and even if they distort the beauty of the gift), we are knowing God in a sublime way that sings to us of eternally ancient glories in the triune being of Father, Son, and Holy Spirit.
The Lord Jesus Christ sang during His earthly life (Matthew 26:30). When the Holy Spirit fills and controls our being, music expressed to God is the result (Ephesians 5:18-19). And the prophet foretells of our Father rejoicing over us with singing (Zephaniah 3:17). Music is thus divine, both in its expression and its origin. Melody, harmony, rhythm, tempo, lyric and their beauty come straight from the heart and mind of God. Every note we will ever hear tells of such wonder, from the devoted saint who sings to express love to his Father, or the unbeliever who enjoys the gift without worshipping the Creator. Again, I know of nothing in creation that more plainly declares that God is. Nor do I know anything that more declares that He is a being of such wonder that even a long eternity will not be adequate to hear the song of His heart singing forth His ineffable beauty.
"Praise ye the LORD. Praise God in His sanctuary: praise Him in the firmament of His power. Praise Him for His mighty acts: praise Him according to His excellent greatness. Praise Him with the sound of the trumpet: praise Him with the psaltery and harp. Praise Him with the timbrel and dance: praise Him with stringed instruments and organs. Praise Him upon the loud cymbals: praise Him upon the high sounding cymbals. Let every thing that hath breath praise the LORD. Praise ye the LORD. "