A Sacrifice of Song
In the Bible, covenants are made by sacrifice (Psalm 50). "Sacrifice" implies not only slaughter and burning, but also a meal. When Israel cuts or enters covenant, they seal it with a meal in the presence of Yahweh.
In Chronicles, music takes on much of the work of sacrifice. Song accompanies ascension offerings. Song is, like sacrifice, a memorial presented to God. Levites do the work (abodah) of music, and music is the new "burden" (massa) they bear, replacing the physical burdens of transporting the tabernacle.
When Asa renews covenant with the Lord, we see another sacrificial function of music: the people sing the covenant oath. Like offering an animal, music is a covenant-making or covenant-entering act. Song is a means of seeking Yahweh; song is also a commitment to seek him.
Think of that next time you open your mouth to sing at church. You're not just expressing your joy in the Lord, though you are doing that. The music doesn't exist only to enhance or elicit your delight in God, though it does that. Your singing is an oath-by-sacrifice, a commitment of body and soul to seek the Lord with everything you've got.
—Peter J. Leithart