When the prophet Habakkuk uses the term in today's reading, he seems to draw a comparison between faithfulness and the lack of it:
. . . his soul is puffed up; it is not upright
The New Testament section was way over my head for the most part, but I did pick up on a reference to faith:
The deeds of the faithful follow them. Habakkuk's comparison between one who is "puffed up" and a righteous person is very pertinent, since endurance and consistency can be a problem for me when it comes to faith. I am moody! Sometimes I feel like pursuing God, and sometimes I don't so much. Some days I'm willing to squeeze in time for prayer and focused Bible reading, and on other days things get in my way. This is a reminder to you and me both. It takes an active, steady effort to live by faith, but our deeds will follow us. It is well worth the time and trouble to keep up the discipline of an active faith!