“Whoever finds lost property, let him ask one or two men of good character to witness it, then he should not alter it nor conceal it. If its owner comes along, then he has more right to it, otherwise it belongs to Allah (SWT), Who gives it to whomsoever He wills.”

The Prophet (ﷺ) said: Pay the deposit to him who deposited it with you, and do not betray him who betrayed you.

The Prophet (ﷺ) said: He who finds something should call one or two trusty persons as witnesses and not conceal it or cover it up; then if he finds its owner he should return it to him, otherwise it is Allah's property which He gives to whom He will.

The Prophet (ﷺ) said, "An Israeli man asked another Israeli to lend him one thousand Dinars. The second man required witnesses. The former replied, 'Allah is sufficient as a witness.' The second said, 'I want a surety.' The former replied, 'Allah is sufficient as a surety.' The second said, 'You are right,' and lent him the money for a certain period. The debtor went across the sea. When he finished his job, he searched for a conveyance so that he might reach in time for the repayment of the debt, but he could not find any. So, he took a piece of wood and made a hole in it, inserted in it one thousand Dinars and a letter to the lender and then closed (i.e. sealed) the hole tightly. He took the piece of wood to the sea and said. 'O Allah! You know well that I took a loan of one thousand Dinars from so-and-so. He demanded a surety from me but I told him that Allah's Guarantee was sufficient and he accepted Your guarantee. He then asked for a witness and I told him that Allah was sufficient as a Witness, and he accepted You as a Witness. No doubt, I tried hard to find a conveyance so that I could pay his money but could not find, so I hand over this money to You.' Saying that, he threw the piece of wood into the sea till it went out far into it, and then he went away. Meanwhile he started searching for a conveyance in order to reach the creditor's country. One day the lender came out of his house to see whether a ship had arrived bringing his money, and all of a sudden he saw the piece of wood in which his money had been deposited. He took it home to use for fire. When he sawed it, he found his money and the letter inside it. Shortly after that, the debtor came bringing one thousand Dinars to him and said, 'By Allah, I had been trying hard to get a boat so that I could bring you your money, but failed to get one before the one I have come by.' The lender asked, 'Have you sent something to me?' The debtor replied, 'I have told you I could not get a boat other than the one I have come by.' The lender said, 'Allah has delivered on your behalf the money you sent in the piece of wood. So, you may keep your one thousand Dinars and depart guided on the right path.' "

That the Prophet (ﷺ) said: "Fulfill the trust for the one who entrusted you, and do not cheat the one who cheated you." This Hadith is Hasan Gharib. Some of the people of knowledge followed this Hadith, they said that when something belonging to a man is with another and he leaves (with it), then he has something that belongs to him, he may not withhold from him an equivalent to what the other took of his. Some of the people of knowledge among the Tabi'in allowed that. This is the view of Sufyan Ath-Thawri, he said: "If one man has some Dirham that belong to another, and the second has some Dinar belonging to the first, he may not withhold any in place of his Dirham, unless it so happens that he has some Dirham of his, then in that case he can withhold some of his Dirham equal to what he is owed by the first."