بسم الله الرحمن الرحيم
After researching the chain of the hadith [i.e. hadith of the "Will"], mentioned in the ‘Kitāb al-G̲h̲ayba’ by Sheikh al-Tusi (ra), Sheikh ‘Alī Āl Muḥsin states the following:
هذه الرواية سندها ضعيف، بل مظلم جدَّاً، وأغلب رواتها مجاهيل، لم يرد لهم ذكر في كتب الرجال، لا بمدح ولا بقدح
"This report, its chain is ḍa’īf [weak], in fact very unreliable, and the majority of its narrators are majāhīl [unknown narrators]. No mention is made of them in the books of al-Rijāl, no praise and no condemnation."
Source: Radd al-qāṣim by Sheikh ‘Alī Āl Muḥsin, page 28,
[Note]: Scholars, who had researched the chain of the hadith, have come to the conclusion, that the hadith has been narrated through Ammah [i.e. Sunnis]. Refer to the article: The "Will" & Ahmad al-Hassan. It should be noted also, that there is another hadith about Prophet's (saw) ''Will''. Refer to the article: Ahmad al-Hassan - mentioned in the "Will"?.
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