"The Messenger of Allah came to visit me while I was sick. He said: 'Do you have a will?' I said: 'Yes.' He said: 'For how much?' I said: 'All of my wealth, for the cause of Allah.' He said: 'What did you leave for your children?'" He (Sa'd) said: "They are rich in goodness.' He said: 'Will a tenth.'" He (Sa'd) said: "He (pbuh) continued decreasing it until he said: 'Will a third, and a third is too great.'" (One of the narrators:) Abdur-Rahman said: "We considered it recommended that it be less than a third, since the Messenger of Allah said: 'And a third is too great.'"
عَادَنِي رَسُولُ اللَّهِ ﷺ وَأَنَا مَرِيضٌ فَقَالَ أَوْصَيْتَ قُلْتُ نَعَمْ قَالَ بِكَمْ قُلْتُ بِمَالِي كُلِّهِ فِي سَبِيلِ اللَّهِ قَالَ فَمَا تَرَكْتَ لِوَلَدِكَ قُلْتُ هُمْ أَغْنِيَاءُ بِخَيْرٍ قَالَ أَوْصِ بِالْعُشْرِ فَمَا زِلْتُ أُنَاقِصُهُ حَتَّى قَالَ أَوْصِ بِالثُّلُثِ وَالثُّلُثُ كَثِيرٌ قَالَ أَبُو عَبْدِ الرَّحْمَنِ وَنَحْنُ نَسْتَحِبُّ أَنْ يَنْقُصَ مِنَ الثُّلُثِ لِقَوْلِ رَسُولِ اللَّهِ ﷺ وَالثُّلُثُ كَثِيرٌ قَالَ وَفِي الْبَابِ عَنِ ابْنِ عَبَّاسٍ