I found something valuable. What am I supposed to do with it?
It depends on what it is and where you found it. The classical rule for something of value is to note its description, announce it publicly for a year, and only then use it — remaining liable to the owner if they appear. Trivial items may be taken. Anything found in the Haram of Makkah has a stricter rule, and today, handing it to the police or lost property usually satisfies the purpose better than announcing it yourself.
The honest answer turns on your circumstances. What it hinges on is below.
Lost property (luqata) has a developed set of rulings, and they turn on the value of the item and where it was found.
The governing report: a man asked the Prophet ﷺ about picking up a lost item, and was told to remember the description of its container and its string, to announce it publicly for a year, and then to use it — but to give it to the owner if he came (Sahih al-Bukhari 2429).
The cases:
1. Trivial items — a stick, a piece of fruit, something nobody would look for. These may simply be taken. 2. Items of value — money, jewellery, a phone, a wallet. Note the identifying details, make a genuine effort to find the owner for a year, and if nobody claims it you may use it, remaining liable to return its value should the owner appear later. 3. Stray livestock that can protect itself was to be left alone. 4. Anything found in the Haram of Makkah is treated more strictly: it is announced indefinitely rather than for a year, and not appropriated.
What your answer turns on: the item's value, where you found it, whether an identifiable owner is realistically findable, and the law where you live.
On that last point — modern circumstances change how the duty is discharged rather than whether it exists. A wallet handed to the police, a phone left with the venue's lost property, or an item logged with a transport operator reaches the owner far more reliably than an announcement, and most scholars regard that as fulfilling the obligation. Where local law requires handing items in, that is generally followed.
The principle underneath all of it: “Indeed, Allah commands you to render trusts to whom they are due and when you judge between people to judge with justice. Excellent is that which Allah instructs you. Indeed, Allah is ever Hearing and Seeing.” (Qur’an 4:58)
One caution worth stating plainly: keeping something valuable you found without any attempt to find the owner is taking someone's property, and the fact that they lost it does not transfer it to you.
- HadithSahih al-Bukhari 2429
- Qur’anQur’an 4:58