Sunan an-Nasa'i, Hadith 3633 ⓘ
It was narrated from 'Aishah that the Messenger of Allah came to visit Sa'd (when he was sick). Sa'd said to him: "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."
أَخْبَرَنَا مُحَمَّدُ بْنُ الْوَلِيدِ الْفَحَّامُ، قَالَ حَدَّثَنَا مُحَمَّدُ بْنُ رَبِيعَةَ، قَالَ حَدَّثَنَا هِشَامُ بْنُ عُرْوَةَ، عَنْ أَبِيهِ، عَنْ عَائِشَةَ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم أَتَى سَعْدًا يَعُودُهُ فَقَالَ لَهُ سَعْدٌ يَا رَسُولَ اللَّهِ أُوصِي بِثُلُثَىْ مَالِي قَالَ " لاَ ". قَالَ فَأُوصِي بِالنِّصْفِ قَالَ " لاَ ". قَالَ فَأُوصِي بِالثُّلُثِ قَالَ " نَعَمِ الثُّلُثَ وَالثُّلُثُ كَثِيرٌ أَوْ كَبِيرٌ إِنَّكَ أَنْ تَدَعَ وَرَثَتَكَ أَغْنِيَاءَ خَيْرٌ مِنْ أَنْ تَدَعَهُمْ فُقَرَاءَ يَتَكَفَّفُونَ ".
also referenced under: Book 30, Hadith 23 (In-Book) & Volume 4, Book 30, Hadith 3663 (DarusSalam)