The Advent devotional I got from Gordon-Conwell Theological Seminary, as a part of their Journey to the Manger advent devotionals, about a week ago, written by Sean McDonough, was a really good one. I know I've shared an advent devotional from GCTS before, but I'd really encourage you to check this one out and be blessed:
Matthew 3:1-12
Of all the many Christmas cards I have seen over the years, I cannot recall a single one that began, “Brood of Vipers...” But some of the people on John the Baptist’s mailing list received just such a message as he prepared them for the Advent of Jesus’ public ministry (Matt. 3:7). What could such a brutal (brood-al?) description have to do with the good news?
In short, everything. The Pharisees and Sadducees in question would never seek transformation until they first realized they needed transforming. Without John’s stinging rebuke, they would go on thinking that the venomous teaching coming from their lips was the sweetest honey. His message is clear: Stop slithering, and straighten out.
The doctor’s diagnosis of a deadly disease can be good news... provided it is followed by the assurance that a certain cure lies at hand. Even so, John’s call to repentance is followed by the promise that one is coming who will baptize with the fiery Holy Spirit, who will burn away the image of the serpent on our souls and emblazon on us anew the likeness of the living God.