What are some of the cultural symbols in "A Very Old Man with Enormous Wings?"

The major
symbol(s) is/are the wings of the possible angel, and have more than one interpretation. Rather
than being a beautiful being of light and spirituality, the angel is old and dirty, and his
wings are missing feathers and full of parasites. His wings are not those of a holy being but of
a working biology; even the doctor, seeing how perfectly the wings fit in with the angel's body,
wonders why wings aren't more common. The angel's specific wings are the focus of attention, as
a different flying person is ignored:

A
traveling...