بسم الله الرحمن الرحيم
Deception of Ahmad al-Hassan, that al-Yamani mentioned in Shia hadith is from the lineage of 12th Imam (as) has failed. In this hadith, we get valuable information, which refutes Ahmad al-Hassan.
When Imam al-Sadiq (as) was asked about the 'signs' before the rise of 12th Imam (as), he (as) mentioned several signs, one of those signs is a man [i.e. al-Yamani] from Yemen, as mentioned by several Imams from Ahl al-Bayt (as). This man [i.e. al-Yamani] is from the lineage of Zayd ibn Ali (ra) and he is a Shīʿah of Ahl al-Bayt (as).
وخروج رجل من ولد عمي زيد باليمن
[Imam al-Sadiq (as) said]: "and the emergence of a man [i.e. al-Yamani] from the lineage of my uncle Zayd from Yemen."
Source: Bihār al-Anwār by Allamah al-Majlisī, Volume 83, page 50, Hadith # 1
 Refer to: Yamani from Yemen.
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