How does the text develop the character of the old man?

When we first meet the old man he is a mystery, but over the course of the story, he transforms from an angel to a side-show act, a proclaimed imposter, and eventually.... he regains his wings and flies away. Rather than be treated with respect, he is treated like an animal. The old man's healing can be seen as a miracle... and his departure is once again.... supernatural.

The people in the story treat him as an oddity, but not a supernatural oddity.... more a freak of nature than something beyond nature. He appears to be nothing more than a frail human with wings, and so his status as an angel is endlessly debated. Father Gonzaga thinks that he cannot be an angel because he lacks dignity and splendor. Of course this begs the question of whether the angel lacks dignity intrinsically, or whether he lacks dignity because of the way he is treated - cooped up in a chicken cage. Perhaps it is the people who lack dignity, not the old man. The old man's other supernatural characteristic - his incredible patience in the face of his treatment - does not make much of an impression on the majority of the people, who are happy to exploit him until bored with him.