If we're talking about minor characters that we're tempted to think have nothing to teach us about being persons of faith, Haman is definitely somewhere near the top of that list.
Haman is the "villain" in the story of Esther, the king's high-ranking official who is so thoroughly disgusted by Mordecai the Jew's unwavering faithfulness to the God of Israel (and not the king) that he devises a plan to hang Mordecai on a giant public gallows and to systematically destroy the entire Jewish people. If ever there were a villain, Haman is a villain. Through and through.
There's this scene in the story where Haman is on his way to the king, very proud of himself for the plan that he has concocted. He's got vengeance in his heart, and it's so close, he can taste it. The hate that he has for Mordecai is right on the tip of his tongue, and he is mere seconds away from finally putting this man out of his sight forever.
Then, he gets to the king and the king speaks before he can. "What should a king do for a man who has been incredibly good to him?" And Haman, of course, thinks the king must be talking about him because who is as good as a man in his own mind? So Haman comes up with the greatest reward, the most public commendation, the thing that he would most like to have done for him...and the king says, "Great. Go give all that to Mordecai. Go do all that for Mordecai."
And Haman goes. And Haman does.
Haman does not stand there and say, "Well, actually, King, that's the very guy I wanted to talk to you about...." He doesn't try to tell his story right then. He doesn't let his own personal distaste for the Jew get in the way of his sense of duty to the king.
And this is really, really remarkable, don't you think?
Haman has every reason in his own heart why Mordecai should not merit such treatment. He has every grudge, every bitterness, every hate telling him not to do this. But his sense of obedience, his sense of duty, that sense of integrity that he has about having committed himself to the service of the king trumps all that and Haman puts Mordecai on an animal and parades him right past the gallows that Haman has erected to hang the man.
We could all learn a little something from that. Couldn't we?