Al-Mustadrak alaa al-Sahihain

Al-Mustadrak alaa al-Sahihain (Arabic: المستدرك على الصحيحين; Al-Mustadrak 'ala al-Sahîhayn‎‎) is a five volume hadith collection written by Hakim al-Nishapuri (Nishapur is located in Iran).

He wrote it in the year 393 AH (1002–1003 CE), when he was 72 years old. It contains 9045 hadith. He claimed all hadith in it were authentic according to the conditions of either Sahih al-Bukhari or Sahih Muslim or both.

The statement of authenticity was not accepted by a number of prominent later Sunni scholars. Al-Dhahabi, a 14th century Sunni Shafi'i Islamic scholar made an abridged version of the collection named Talkhis al-Mustadrak where he commented on its authenticity. It has become the habit of scholars today working in the field of hadîth, when compiling them and determining their authenticity, to say things like "It is authenticated by al-Hâkim and al-Dhahabî concurs". In doing so, they are referring to al-Dhahabi's Talkhîs, his abridgement of the Mustadrak that is often published along with it in its margins.

Dhahabi also wrote:

The Mustadrak contains a good number of hadîth that conform to the conditions of authenticity of both (al-Bukhârî and Muslim) as well as a number of hadîth conforming to the conditions of either one of them. Perhaps the total number of such hadîth comprises half the book. There is roughly another quarter of the hadîth that have authentic chains of transmission, but that have something else about them or that have some defect. As for the rest, and that is about a fourth, they are rejected and spurious narrations that are unauthentic. Some of those are fabrications. I came to know of them when I prepared an abridgement of the Mustadrak and pointed them out.

al-Dhahabi lamented:

It would have been better if al-Hakim had never compiled it."

Ibn Hajar al-Asqalani, a 15th century Sunni Islamic scholar states that Mawdu'at al-Kubra is as unreliable in its attributing the grade of being "forged" to certain ahadith as al-Hakim's Mustadrak is unreliable in its declaring the grade of "sound" or Sahih to many ahadith.

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