The author is Abu Bakr Ahmed ibn Hussain ibn ‘Ali al Bayhaqi (d. 458 A.H). These asanid are quoted from ‘Abaqat al Anwar (vol. 1 pg. 215).
Akhtab Khawarizmi (d. 571 A.H) has reported in Manaqib from Ahmed ibn Hussain bin ‘Ali al Bayhaqi:
اخبرنا ابو عبدالله قال حدثنا ابو نصر احمد بن سهيل الفقيه ببخارى قال حدثنا صالح بن محمد الحافظ قال حدثنا خلف بن سالم قال حدثنا يحيى بن حماد قال حدثنا ابو عوانة عن سليمان الاعمش قال حدثنا حبيب بن ابى ثابت عن ابى الطفيل عن زيد بن ارقم رضى الله عنه قال لما رجع رسول الله صلى الله عليه و سلم عن حجة الوداع و نزل بغدير خم امر بدوحات قد تركت فيكم الثقلين احدهما اكبر من الاخر كتاب الله وعترتى اهل بيتى فانظروا كيف تخلفونى فيهما
Abu ‘Abdullah — Abu Nasr Ahmed ibn Suhayl al Faqih — Salih ibn Muhammad al Hafiz al Baghdadi — Khalaf ibn Salim al Makhrami — Yahya ibn Hammad — Abu ‘Awanah —Sulaiman al A’mash — Habib ibn Abi Thabit — Abu al Tufayl — from Zaid ibn Arqam radiya Llahu ‘anhu:
Whilst returning from Hajjat al Wada’, Nabi salla Llahu ‘alayhi wa sallam disembarked at a pond called Khum. He ordered that the trees of the area should be trimmed. (Thereafter he addressed the people saying:) “I am leaving amongst you al Thaqalayn, one is of greater weight than the other. They are the Book of Allah and my ‘itrah, who are my Ahlul Bayt. Be careful of how you treat them in my absence.”
The readers should be aware that this isnad of Abu Bakr al Bayhaqi is identical to the second isnad of Mustadrak. The details regarding it have already been mentioned there. The crux of it is that Khalaf ibn Salim al Makhrami appears in the isnad. According to the muhaddithin, he was a Shia who had a passion for collecting the ‘mistakes’ of the Sahabah. This passion was a result of deep inner feelings. The scholars can refer to Taqrib al Tahdhib and Tahdhib of Ibn Hajar al ‘Asqalani as well as Tarikh Baghdad of al Khatib. Detailed references were given under the second isnad of Mustadrak al Hakim. Therefore, the appearance of a single Shia narrator of this category is sufficient to regard it as unacceptable. Criticism can be levelled against a few other narrators of this isnad as well; however, we suffice with what has been mentioned, since we wish to keep this treatise as concise as possible.
1. Akhtab Khawarizmi (565-571 A.H) himself needs to be discussed. We will reproduce the exact words of Ibn Taymiyyah and Shah ‘Abdul ‘Aziz regarding his narrations to the readers. Ibn Taymiyyah writes in Minhaj al Sunnah:
ان اخطب خوارزم هذا له مصنف فى هذا الباب فيه من الاحاديث المكذوبة ما لا يخفى كذبه على من له ادنى معرفة بالحديث فضلا عن علماء الحديث وليس هو من علماء الحديث ولا ممن يرجع اليه فى هذا الشان البتة
Akhtab Khawarizmi compiled a book (called Manaqib) regarding the merits of ‘Ali radiya Llahu ‘anhu and the Ahlul Bayt which comprises of many fabricated narrations. Those who have the slightest knowledge regarding hadith will be able to tell that they are fabricated let alone one who is a specialist in the science of hadith. Akhtab is neither a scholar of hadith, nor is he amongst those who are referred to regarding the subject.
A summary of what has been mentioned in Tuhfah Ithna ‘Ashariyyah is as follows:
Ibn Mutahhar al Hilli attributed the narration:
من ناصب عليا في الخلافة فهو كافر
Whoever opposes the Caliphate of ‘Ali radiya Llahu ‘anhu is a kafir.
to Akhtab Khawarizmi. Ibn Mutahhar deceives abundantly when reporting narrations. Reporting this from Akhtab Khawarizmi is sufficient for it to be disregarded. Akhtab Khawarizmi is an extremist Zaidi Shia. Nevertheless, the above narration is not mentioned in his book, Manaqib, which was compiled regarding the merits of Amir al Mu’minin ‘Ali radiya Llahu ‘anhu. This narration is definitely not in his book. However, if we have to accept that it is in his book, then too it is not authentic. This is because his narrations contradict the ‘authentic’ narrations of the Shia as well.
Shah ‘Abdul ‘Aziz says that the Muhaddithin of the Ahlus Sunnah are unanimous upon the fact that all the narrations of Akhtab Zaidi are from unreliable and unknown sources. Most of the narrations contradict those of reliable narrators and they are fabricated. The fuqaha’ of the Ahlus Sunnah definitely do not use his narrations as evidence.
2. The author of ‘Abaqat presented this narration and the narration of al Hakim separately, whereas they are identical. This was done so as to give the readers the impression that there are many references for it. He employed these deceitful tricks to lengthen his book, which he managed, and thus managed to compile a voluminous book just on this one narration (of Thaqalayn).
The author of ‘Abaqat states:
Al Bayhaqi narrated this hadith from Zaid ibn Arqam. Hamawi states in Fara’id al Simtayn:
ا خبرنا الامام الشيخ ابو بكر احمد بن حسسين بن على البيهقى قال انبانا ابو محمد جناح بن نذير بن جناح القاضى بالكوفة قال انبانا ابو جعفر محمد بن على بن رحيم قال انبانا ابراهيم بم اسحاق الزهرى قال انبانا جعفر يعنى ابن عون و يعلى عن ابن حيان التيمى عن يزيد بن حيان قال سمعت زيد بن ارقم قال قام فينا رسول الله صلى الله عليه و سلم خطيبا فحمد الله و اثنى عليه فقال اما بعد ايها الناس انما انا بشر يوشك ان ياتينى رسول ربى و انى تارك فيكم الثقلين كتاب الله فيه الهدى و النور فاستمسكوا بكتاب الله وخذوا به فحث على كتاب الله و رغب فيه ثم قال اذكركم الله تعالى فى اهل بيتى ثلالث مرات اخرجه مسلم فى الصحيح من حديث ابى حيان التميمى
Abu Bakr Ahmed ibn Hussain ibn ‘Ali al Bayhaqi — Abu Muhammad ibn Janah ibn Nadhir ibn Janah al Qadi — Abu Jafar Muhammad ibn ‘Ali ibn Rahim — Ibrahim ibn Ishaq al Zuhri — Jafar (ibn ‘Aun) and Ya’la — Abu Hayyan al Taymi — Yazid ibn Hayyan — that Zaid said:
Once Rasulullah salla Llahu ‘alayhi wa sallam stood up to deliver to us a sermon. He praised Allah abundantly. Thereafter he said, “O people, Indeed I am only a human. Soon the messenger of my Rabb will come to me. Indeed I will leave amongst you al Thaqalayn, the first one being the Book of Allah, in it is guidance and illumination, so hold onto the Book of Allah and never let it go.” He continued to encourage and explain regarding the Book of Allah. Then he added, “I remind you to fear Allah regarding my household.” he said this thrice. Narrated by Muslim in his Sahih-the hadith of Abu Hayyan al Taymi.
Firstly, it should be known that there are many such persons who appear in this isnad whose details cannot be found in the books of rijal. We could not find any detailed write up about the teacher of Bayhaqi, Janah ibn Nadhir. After much searching, we could only find that he was amongst the teachers of al Bayhaqi. Thereafter, the details of the teacher of Janah, Abu Jafar Muhammad ibn ‘Ali is nowhere to be found. Similarly, his teacher Ibrahim ibn Ishaq al Zuhri is also unknown. Despite extensive research, we were unable to find his details. Therefore, how can we accept a narration which has so many unknown narrators?
Secondly, if we ignore the isnad and concentrate only on the text of this hadith, then the correct interpretation is the same as that already explained in detail under the hadith of Muslim. The necessary explanation was presented along with the hadith of Muslim. The same explanation applies here as well and there is no need to repeat it.
 Minhaj al Sunnah vol. 3 pg. 101, Chapter 10
 Tuhfah Ithna ‘Ashariyyah hadith six, the discussion of Imamah.
 Vol. 10 pg. 114