Do not neglect to show hospitality to strangers, for by doing that some have entertained angels without knowing it. — Hebrews 13:2.
One of the great stories that came out of 9/11 was the hospitality shown to so many travelers stranded in Gander, Newfoundland. I bet you know someone who is constantly welcoming strangers into his/her home or finding ways to help people who they will never meet again. I have a friend who was moved to help refugees passing through Charlotte on the way to their final destination. She and her children would meet the bus of refugees at midnight with clothes for children and food for their journey.
The author of Hebrews says that my friend may have entertained angels. I think the author got it backwards. The refugees on those buses met an angel in the person of my friend.