"O Messenger of Allah, shall I bequeath two-thirds of my wealth?" He said: "No." He said: "Shall I bequeath half?" He said: "No." He said: "Shall I bequeath one-third?" He said: "Yes, one-third, and one-third is much or large. If you leave your heirs independent of means that is better than if you leave them poor, holding out their hands."
Sunan an-Nasa'i Book 30, Hadith 23