Allah's Messenger (ﷺ) said, "It is not permissible for any Muslim who has something to will to stay for two nights without having his last will and testament written and kept ready with him."
Sahih al-Bukhari Book 55, Hadith 1
← Previous Hadith Umar bin Khattab got some land in Khaibar and he went to the Prophet (ﷺ) to consult him about it saying, "O Allah's Messenger (ﷺ) I got some land in Khaibar better than which I have never had, what do you suggest that I do with it?" The Prophet (ﷺ) said, "If you like you can give the land as endowment and give its fruits in charity." So `Umar gave it in charity as an endowment on the condition that would not be sold nor given to anybody as a present and not to be inherited, but its yield would be given in charity to the poor people, to the Kith and kin, for freeing slaves, for Allah's Cause, to the travelers and guests; and that there would be no harm if the guardian of the endowment ate from it according to his need with good intention, and fed others without storing it for the future."

Sahih al-Bukhari Book 54, Hadith 24 Next Hadith → (The brother of the wife of Allah's Messenger (ﷺ). Juwaira bint Al-Harith) When Allah's Messenger (ﷺ) died, he did not leave any Dirham or Dinar (i.e. money), a slave or a slave woman or anything else except his white mule, his arms and a piece of land which he had given in charity .

Sahih al-Bukhari Book 55, Hadith 2