Preaching in Song

As we discussed the Lewis paper in class on Tues. a few connecting thoughts came into my head. When a preacher does his role rightly and speaks the Word, Truth will penetrate minds, hearts, even souls, and the result will be conviction of sin, repentance, and changed lives. This is true worship according to Romans 12:1-2 -- that we be living sacrifices seeking conformity to the Truth as it is seen and revealed in scripture and in Christ. Certainly we may acknowledge that this is not often comfortable. But it is always good and pure and true and right and admirable and holy. It is indeed the necessary job of the preacher to make the flock uncomfortable at times, to break the legs of the sheep if they are found to be habitual wonderers. If, then, it is true, as we have said in the past, that the song texts in congregational worship are "the other sermon" does it then stand to reason that our worship in singing might not always be comfortable by design or reception?