Sunan Ibn Majah 2711
سنن ابن ماجه#2711SahihIt was narrated that Ibn Abbas said:“I would like the people to reduce (the will) from one third to one quarter, because the Messenger of Allah (ﷺ) said: 'One third is a lot.'”
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Al-AlbaniSahih
Muhammad Fouad Abd al-BaqiSahih
Shuaib Al ArnautSahih
Zubair Ali ZaiSahih - Agreed Upon
In-book reference: 22:17