By the end of December, I will have prepared and delivered fifteen sermons or devotions for services during this month. These are for our Sunday Divine Service, as well as Matins and Vespers services for Advent and Christmas.
But in the midst of a month of near constant preparation to preach, a preacher needs a few sermons, too. I have been able to find those in the church cantatas of Johann Sebastian Bach. I have become particularly attached to two cantatas for Advent, Nun komm, der Heiden Heiland (Savior of the Nations, Come) BWV 61 and Bereitet die Wege, bereitet die Bahn! BWV 132. The librettos for these works, one by Erdmann Neumeister (God’s Own Child I Gladly Say it) and the other by Salomo Franck are just incredible.
Both cantatas are on volume 7 of the collection of church cantatas by the Bach Collegium Japan. I highly recommend these recordings of all of Bach’s cantatas. [If I can figure it out, I’ll add a widget to this post that will allow you to preview this album.]
A Shepherd's Story 
Well that’s interesting – I was just reading something two days ago about the first one you mentioned! I ended up purchasing it (by a different artist though – I know nothing about how to appreciate classical music) and since I couldn’t understand anything I looked up the words (which I had just read about and that is what intrigued me.