Concordia Publishing House has a good blog going, with sections titled worship, read, study, teach, and serve.
I came across a post by Mason Vieth (no relation!), who quoted Luther’s commentary on the Christmas text in Luke. He considers this verse: “And this will be a sign for you: you will find a baby wrapped in swaddling cloths and lying in a manger” (Luke 2:12). How are the manger and the swaddling clothes “a sign”? What do they signify? And Luther brings it around to vocation.
Luther - Luke
From What Luther Says About Luke 2:15-20:
“What it means to find Christ in such poverty, and what His swaddling clothes and manger signify, are explained in the previous Gospel [Luke 2:1–14]. His poverty teaches us to find Him in...