**Frankly, you should have turned it in. The money is not yours to keep.
In the UK money found is to be turned in to the police. If unclaimed after 6 months it is given back to the finder. **
Good advice, but maybe a little too good?
We’re talking about a $50 bill, found on the ground, with no wallet or purse,
no i.d., no cars nearby. It could have been blown there by the breeze from another location. How in the world could anybody reaonably “prove” to the police,
in such a situation, that they had been the one who lost that money???
They would have to keep the exact bill in an evidence bag, letting nobody touch it,
so as to preserve any identifiable fingerprints on it. And after everybody had touched it between the time it was found and the time it was turned in to the police, how could they ever prove even fingerprint evidence?? This rule seems silly to me, especially for small amounts of money like a $50 bill.
I think the O.P. should ask God to restore the money, somehow, to the person who lost or dropped it, especially if they are needy people, and then say a sincere prayer, such as a Chaplet of the Divine Mercy, for the salvation and financial security of whoever lost the money, and then put it out of his mind. He has done no wrong and didn’t steal anything.
But if his conscience is still eating away at him, then for crying out loud, get another $50 bill and turn it in to the cops telling them someone lost $50. He doesn’t have to tell them that he spent the ORIGINAL bill, cuz that doesn’t make a darned bit of difference.