The people who demonstrate courage the most often in The Book of Jeremiah are Jeremiah himself and the people who help him—particularly, Baruch and Ebed-melech. Ebed-melech speaks up in support of Jeremiah while he's in prison and successfully wins his freedom, and Baruch risks his own life helping Jeremiah. Given how unpredictable the rulers are, it was a big risk to stand up to them on someone's behalf. A person could get killed.
Jeremiah personally demonstrates pretty amazing courage throughout his prophetic life. He delivers an unpopular message that he doesn't particularly want to give, and risks everything in the process. He's constantly getting arrested, thrown into pits, and threatened with death. His commitment to the cause has nothing to do with his own personal well-being. It's completely related to the need to tell the truth, since the word of God burns in him "like fire." He has second thoughts a bunch of times, but God encourages him to keep on keeping on.
Questions About Courage
What motivates courageous characters like Baruch and Ebed-melech—or Jeremiah, for that matter?
Do you think that you would personally have the courage to say the sort of unpopular things Jeremiah did?
Who are the modern-day "prophets" who risk it all to spread the word about something they believe in?