What is an expository song?
In an expository song, the main idea of a passage of Scripture is the main idea of the song.
Why are expository songs important?
Colossians 3:16 says: “Let the word of Christ dwell in you richly in all wisdom; teaching and admonishing one another in psalms and hymns and spiritual songs, singing with grace in your hearts to the Lord.”
These are not random, disconnected phrases. A good expository song is a song in which the word of Christ dwells richly.
For better and for worse, the theology of the average Christian is generally as strong as the theology in the songs he sings. Songs are usually the only theology people memorize.
Some churches influenced by American business growth techniques base their sermons and their music on felt needs, pop culture trends, and anything else that might draw a crowd. But an increasing number of churches instead preach through the Bible with sermons where the main idea of the passage is the main idea of the sermon. This is called expository preaching.
Yet the songs that precede and follow these expository sermons are often still based on the felt-needs pop-culture approach.
There is great potential for increased impact by combining a sermon with songs that support its message. Doctrinally solid songs related to the preacher’s sermon can back him up in a way that even good random songs cannot.
A cautionary note
Scripture never requires Christians to only sing expository songs. So it would be unwise to restrict a church’s worship solely to expository songs matching that week’s message. Also, most people need to sing a song more than once to learn it. So there is great wisdom in singing the finest Christian songs, whether or not expository, more than once every twenty or thirty years.