The Prophet (ﷺ) visited me at Mecca while I was ill. I said (to him), "I have property; May I bequeath all
my property in Allah's Cause?" He said, "No." I said, "Half of it?" He said, "No." I said, "One third of
it?" He said, "One-third (is alright), yet it is still too much, for you'd better leave your inheritors
wealthy than leave them poor, begging of others. Whatever you spend will be considered a Sadaqa for
you, even the mouthful of food you put in the mouth of your wife. Anyhow Allah may let you recover,
so that some people may benefit by you and others be harmed by you."
Sahih al-Bukhari Book 69, Hadith 4