1. A question was once posed to Imaam Abu Haneefah (rahmatullahi `alayh) whilst seated in the presence of his Ustaadh Imaam A`amash (rahmatullahi `alayh) who was himself an expert in the science of Qiraat and Hadeeth. After answering the question, his Ustaadh Imaam A`amash asked him to furnish evidence for his answer. In support of his answer, Imaam Abu Haneefah began quoting Ahaadeeth which he had heard from Imaam A`amash himself, with their complete chain of transmission up to Rasulullah Sallallahu Alayhi Wasallam. When he completed the sixth Hadeeth, Imaam A`amash stopped him saying, “This is enough, you have narrated to me in a short space of time what I have narrated to you over a period of one hundred days. I never expected you to be practicing on all these Ahaadeeth.

يا معشر الفقهاء ! أنتم الأطباء ونحن الصيادلة

Oh Fuqahaa (jurists)! You are the physicians and we (the narrators of the Ahaadeeth) are the dispensers.” (He meant that the narrators of Ahaadeeth merely narrate the Ahaadeeth just as a pharmacist dispenses medication, but the Fuqahaa show the application of these Ahaadeeth just as a doctor prescribes the appropriate medication for the appropriate illness). Thereafter Imaam A`amash addressed Imaam Abu Haneefah saying:

وأنت أيها الرجل أخذت بكلا الطرفين

“But you have achieved both aspects (i.e. you are a Muhaddith and a Faqeeh; you narrate Ahaadeeth and also explain its correct application).” (Manaaqibul Imaamil A`azam – `Ali Al-Qaari, with Al- Jawaahirul Mudeeah, vol. 2, pg. 484).

2. Imaam Ahmad bin Hambal (rahmatullahi `alayh) was once asked, “Can a man be called a Faqeeh (jurist) if he commits one hundred thousand Ahaadeeth to memory”? He replied, “No.” The man then enquired: “What about two hundred thousand?” He replied in the negative. He then asked again: “Three hundred thousand?” Imaam Ahmad replied in the negative again. “What about four hundred thousand,” the man asked? Imaam Ahmad gestured with his hand, implying that perhaps this person may qualify to be a jurist and Mujtahid who will issue Fatwas to the people. (I`ilaamul Muwaqqi`een vol. 1, pg. 36).

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A similar incident occurred with Yahya bin Ma`een (rahmatullahi `alayh). He also replied in the negative until the questioner inquired about memorising five hundred thousand Ahaadeeth. Thereupon he said: “I have hope that such a person may qualify.” (Al-Jaami`u li Akhlaaqir Raawi wa Aadaabis Saami`, pg. 345).

In one narration five hundred thousand has also been reported from Imaam Ahmad (rahmatullahi `alayh). (Al-Musawwadah, Atharul Hadeethish Shareef, pg. 175).

When we examine the stature of Imaam Abu Haneefah and his calibre, we find that it is an indisputable fact that he was one of the greatest jurists. The Muhaddith and Faqeeh (jurist) par excellence Sufyaan Thauri (rahmatullahi `alayh) said regarding him:

أفقه أهل الأرض

“Abu Haneefah is the greatest jurist on the surface of the earth.” (Qawaa`id fi `Uloomil Hadeeth, pg. 310). Abdullah bin Mubaarak (rahmatullahi `alayh) says:

أفقه الناس أبو حنيفة ، ما رأيت في الفقه مثله

“Abu Haneefah is the greatest jurist; I did not see the like of him in fiqh (jurisprudence).” (Tahdheebut Tahdheeb, vol. 10, pg. 450). Imaam Shaafi`ee (rahmatullahi `alayh) says:

الناس عيال في الفقه على أبي حنيفة

“Every person is indebted to Abu Haneefah in fiqh (jurisprudence).” (Tahdheebut Tahdheeb, vol. 10, pg. 450). Thus, if memorising five hundred thousand Ahaadeeth is the minimum requirement to qualify as a Faqeeh (jurist), one could imagine how many Ahaadeeth Imam Abu Haneefah must have memorized to receive such a high rank amongst the jurists, and to be titled “The greatest jurist”. Haafiz Abu Yahya Zakariyya Naysaaburi (rahmatullahi `alayh) in his kitaab Manaaqibu Abi Haneefah quotes the statement of Imaam Abu Haneefah:

عندي صناديق من الحديث ، ما أخرجت منها إلا اليسير الذي ينتفع به

“I have many trunks full of Hadeeth. However I have only narrated a small portion of it which people can easily benefit from.” (Al-Imaam Ibnu Maajah wa Kitaabuhu As-Sunan, pg. 54).

3. Mis`ar bin Kidaam (rahmatullahi `alayh) was a great Muhaddith and a contemporary of Imaam Abu Haneefah. He possessed such expertise in the field of Hadeeth that great Imaams like Shu`bah and Sufyaan Thauri (rahmatullahi `alayhima) (both of whom were known as Ameerul Mu’mineena fil Hadeeth-leader of the believers in the science of Hadeeth) would refer to him when they would differ amongst themselves regarding any matter of Hadeeth. They would address each other saying: “Let us go to the Meezaan (criterion) Mis`ar bin Kidaam.” (Al-Imaam Ibnu Maajah wa Kitaabuhu As-Sunan, pg. 50). He once commented:

طلبت مع أبي حنيفة الحديث فغلبنا ، وأخذنا في الزهد فبرع علينا ، وطلبنا معه الفقه فجاء منه ما ترون

“I studied Hadeeth with Abu Haneefah and he surpassed us. We focused on piety and abstention from the world and in this also he excelled. Then we studied fiqh (jurisprudence) together with him and in this also he has produced such results that are clearly visible to you.” (Manaaqibu Abi Haneefah – Zahabee, pg.27). It is a common fact that one of the greatest compliments is the compliment of a contemporary, because generally rivalry exists between contemporaries. Furthermore, in this instance the contemporary is no ordinary person. Instead he is a great expert in the field of Hadeeth. This is further supported by the statement of Makki bin Ibraaheem and Yazeed bin Haaroon (rahmatullahi `alayhima) in which they said:

أحفظ أهل زمانه

“Abu Haneefah was the greatest Haafiz of Hadeeth in his time.” (Ibne Maajah aur `Ilme Hadeeth, pg. 166).

4. As was the prevalent custom amongst the great luminaries of the past where they contributed to the field of Hadeeth by compiling the Ahaadeeth of Nabi Sallallahu Alayhi Wasallam in a book form, similarly did Imam Abu Haneefah accomplish this feat by compiling his widely acclaimed kitaab, “Kitaab-ul-Aathaar”. However, the unique feature of this kitaab is that it is compiled in a systematic format following the sequence of the chapters of fiqh that is commonly followed by the Fuqahaa and Muhadditheen who came later. Moreover, it covered every chapter that one would normally find in the books of fiqh. On the other hand, the compilations prior to the compilation of Imam Abu Haneefah were not systematic; rather they covered different Ahaadeeth without any specific chapter or topic. Similarly, there were other compilations that did have a sequence to some extent, but only covered a few topics. Thus the oldest systematic compilation of Saheeh Ahaadeeth that is found today is the Kitaab-ul-Aathaar of Imam Abu Haneefah. (Ibne Maajah aur `Ilme Hadeeth, pg. 159).

He selected the Ahaadeeth therein from a collection of forty thousand Ahaadeeth. (Ibid, pg. 164).

Besides Kitaab-ul-Aathaar, there are approximately fifteen compilations that contain the Ahaadeeth of Imam Abu Haneefah. (Sharhu Musnadi Abi Haneefah – `Ali Al-Qaari, pg. 7).

Mulla `Ali Qaari (rahmatullahi `alayh) writes: The Mashaayikh (teachers) of Imam Abu Haneefah total up to four thousand. (Ibid, pg.8)

Source: https://islambestreligion.wordpress.com/2011/02/22/a-glimpse-of-imam-abu-haneefahs-ra-expertise-in-the-science-of-hadeeth/