Ahmad 590

Its isnad is sahih. Abu Yusuf the tutor, neighbor of Imam Ahmad, is Yaqub bin Isa bin Mahan, of Marw origin. Ibn Hibban mentioned him among the trustworthy, and Khatib gave his biography in Tarikh Baghdad 14:271-272.Abdul-Aziz bin Muttalib bin Abdullah bin Hantab, Ibn Hibban mentioned him among the trustworthy, Ibn Main said he was upright, and Abu Hatim said his hadith was sound. He held the judgeship of Madinah in the time of Mansur and then Mahdi, and he also held the judgeship of Makkah. Zubayr bin Bakkar described him as generous and knowledgeable in judgment and adjudication.Abdul-Rahman is Ibn Harith bin Abdullah bin Ayyash, and he is trustworthy, a man of knowledge.Zayd bin Ali bin Husayn is the one to whom the Zaydis trace their name. He is trustworthy, and he used to disavow the Rafidah.What appears clear from this isnad is that the hadith belongs to the musnad of Husayn bin Ali, not to the musnad of his father Ali bin Abu Talib, because Zayd relates it from his father Ali Zayn al-Abidin, from his grandfather, who is Husayn bin Ali. This is likewise stated explicitly in Majma al-Zawaid 6:244, where it is classified as a hadith of Husayn bin Ali, and it is said there that its narrators are trustworthy.Khatib narrated the hadith in the biography of Abu Yusuf the tutor by the route of this musnad, and he added to it other routes that all converge on this same Abu Yusuf.