There is a Biblical verse relevant to this story which states,
Be not forgetful to entertain strangers: for thereby some have entertained angels.
Marquez's story has, indeed, timeless themes such as the need to find explanations, the need to simplify, the supernatural, the role of religion, old age, and "The Other." Certainly, in each there is the undertone of morality. The people of the village try to explain the inexplicable in terms with which they are familiar and identify what is of value. When the old man with enormous wings cannot be categorized, the people reject him and devalue him:
...the few miracles attributed to the angel showed a certain mental disorder, like the blind man who didn't recover his sight but grew three new teeth.....Those consolation miracles, which were more like mocking fun....
What surprised most...was the logic of his wings. They seemed so natural on that completely human organism that he couldn't understand why other men didn't have them too.
Further, the existence of the old angel evolves into a carnival atmosphere. Pelayo and Elisenda exploit him as a freak, acting immorally as they sell tickets and profit from his misfortune and that of others such as the spider woman. Of course, the reader discerns the irony of this situation as it was the appearance of the angel that seems to have effected the cure of the baby and taken Pelayo and his wife out of poverty. Then Father Gonzaga arrives and announces that the angel "should be named mayor of the world." Others think that he should be "promoted to the rank of five-star general in order to win all wars." They wish to exalt themselves vicariously through this strange being--another instance of exploitation and an immoral act.
"The angel was the only one who took no part in his own act." This situation certainly calls into question the morality of those who exploit him. But he tolerates "the most ingenious infamies" and, finally, heals enough to fly off. Ironically Elisenda is grateful that the "annoyance" that has provided her with a beautiful home is gone.