Hadith.5477 - It is narrated by Al-Bazanti from Al-Husayn ibn Khalid, who said:
I asked Abu Al-Hasan عليه السلام about a man who bequeathed a portion of his wealth.
Imam عليه السلام replied: "It is one-seventh of his one-third share."
The author of this book, may Allah سبحانه وتعالى have mercy on him, explains that in the past, wealthy individuals would divide their wealth into portions. Some would divide their wealth into ten parts, while others would divide it into seven.
Therefore, a person's will should be executed according to how they customarily divided their wealth. Such specific forms of bequests are usually made by those well-versed in language and understanding. However, for the majority of people, wills are generally made in clear and specific terms that require no further interpretation.
If a person makes a will or vows to give away "a large amount" of wealth, then the interpretation of "a large amount" is considered to be eighty or more, based on the verse of Allah سبحانه وتعالى, the Exalted: "Indeed, Allah سبحانه وتعالى has given you victory in many (kathirah) battlefields" (Surah At-Tawbah 9:25), where "many" referred to eighty instances of victory.