In Leo Tolstoy's short story "What Men Live By," the angel Michael learns that people dwell best when in love and that they do not always know what is in their best interests. Michael also learns that people live best by loving others and not by focusing solely on themselves.
The angel Michael admits toward the end of "What Men Live By" that God banished him to Earth in order to learn three things. He learns each lesson through his association with Simon the shoemaker, who found the angel naked and alone on a cold street. Simon didn't expect to gain anything by the charitable act, and for this kindness, Michael made sure that Simon succeeded as a shoemaker and had more than enough to care for and feed his family.
Michael smiles each time he learns one of the three truths he must learn before he can return to Heaven. He smiles the first time when Simon and his wife welcome him into their home. He smiles for the second time when he makes a pair of slippers for a man who had ordered boots. Michael makes slippers because he knows the man is about to die and needs the slippers. The third time Michael smiles is when he hears the story of orphaned twins who were taken in by a stranger who cared for them as if they were her own.
After hearing this story, Michael confesses to Simon who he is and why he is on Earth, explains the three truths he learned and urges Simon to live a love-filled life. Michael then returns to Heaven.