R’ Shmuel Ben Sasorte was an Amoraic sage in Eretz Yisroel, who once traveled to Rome. As he neared the city, he suddenly noticed a string of expensive pearls lying on the road. He picked up the gems and placed it in his pocket, thinking to himself that it certainly belonged to a wealthy person, and wondering who that might be. Further down the road he beheld a large crowd gathered around to hear a royal proclamation.
“It shall be known to all citizens of Rome that Her Majesty lost her pearl necklace in the streets of Rome. If the finder returns it within thirty days he shall be richly rewarded; if the finder comes after thirty days he shall be put death.”
This was repeated several times so that the maximum amount of people should be notified of the news.
R Shmuel listened closely to the proclamation, and knew right away that he was the finder, and that if he returned it immediately he would be rewarded. But he was in no hurry.
Day after day, R’ Shmuel heard the announcement promising reward and threatening a cruel punishment, but still he was in no hurry to return the valuable necklace.
Finally on the thirtieth day he took out the necklace, polished it with care, and proceeded to safely put it away again.
Early the next morning, immediately after davening, he went to the palace to report his find. He was ushered into the queen’s presence.
R’ Shmuel presented the necklace to the queen who was filled with excitement at finally being reunited with her prized treasure. For a moment, she was full of gratitude, until she remembered that it was the thirty first day since the first proclamation.
“When did you find the necklace?” asked the queen.
“Thirty one days ago.”
“Were you in Rome for the last month?”
“Did you hear the daily announcements about the reward and punishment?”
“Yes, Your Majesty.”
“So then why did you risk your life, instead of collecting a handsome reward?”
“Your Majesty, if I would have brought the necklace within thirty days, it would have appeared that I returned the necklace either to receive reward or to avoid punishment. In truth however, neither are correct. I returned your necklace simply because our Torah commanded us to return lost property. We are happy to fulfill the Torah’s commandments without reward, and we are prepared to die for its observance.”
The queen was immensely impressed by R’ Shmuel’s words and not only did she not order his death, rather he was accorded great honor for his pure honesty.
Of course lost objects should be returned at the first possible opportunity, but R’ Shmuel wanted to drive the point home that his only concern was for the observance of Torah, and not of worldly consequences.
 The Storyteller Vol. 5 page 271.