The image and witness of John the Baptist informs us that the call of this Advent season is for us to break out of whatever our comfortable space is and to process to encounter the Christ Mass with neediness and zeal and abandon.
In regards to our call to keep watch and to be on guard (i.e. for ourselves and for the community) against those things that might harm the house of the Lord (i.e. ourselves and the Church), there are three reasons why we tend to fail to do so consistently.