Music (which you're confusing with lyrics) is merely a tool used in facilitating praise to God. I have a problem with songs that "edify us" because that time isn't about us, it's about God. Besides, we're supposed to edify one another, not ourselves and there's nothing in scripture that says the songs we sing are supposed to edify ourselves.

Notice Colossians 3:16, "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." Of course, some have suggested the passage should contain the comma after "another" instead of after "songs."

Then there's Ephesians 5:19-20, "Speaking to yourselves in psalms and hymns and spiritual songs, singing and making melody in your heart to the Lord; Giving thanks always for all things unto God and the Father in the name of our Lord Jesus Christ."