Sayid Muhammad Ridha al Shirazi narrates a story of a poor Muslim who found a ring belongs to a Christian and returned it to him.
The Christian asked whether he is poor; he said: yes.
“Do you know that I am a Christian?” He said: “Yes”.
“Well, I woukd be impossible to know that you found the ring, why did’t you just take it?” The Christian wondered.
He replied: “I thought about it in the beginning but then I thought that on the Day of Resurrection, you may come with your Prophet, and I will come with my Prophet; perhaps your Prophet woukd complain to my Prophet that one of your follows took a ring for one of my followers. So I thought that your in not worth of upsing my Prophet, so I didn’t take the ring.” The poor Muslim said.