Our Fiqh is unique in the sense that our opponents have themselves accepted that it is authentically narrated from Ahl ul Bayt (as) as claimed by Imamiyyah. Here are few testimonies :
1. Ibn Qayyim al-Jawziyya :
Imam Ibn al Qayyum [ Famous Student of Ibn Tahmiyyah] says :
إن فقهاء الإمامية من أولهم إلى آخرهم ينقلون عن أهل البيت أنه لا يقع الطلاق المحلوف به وهذا متواتر عندهم عن جعفر بن محمد وغيره من أهل البيت.
وهب أن مكابرا كذبهم كلهم وقال قد تواطئو على الكذب عن أهل البيت ففي القوم فقهاء وأصحاب علم ونظر في اجتهاد وإن كانوا مخطئين مبتدعين في أمر الصحابة فلا يوجب ذلك الحكم عليهم كلهم بالكذب والجهل وقد روى أصحاب الصحيح عن جماعة من الشيعة وحملوا حديثهم واحتج به المسلمون ولم يزل الفقهاء ينقلون خلافهم ويبحثون معهم والقوم وإن أخطأوا في بعض المواضع لم يلزم من ذلك أن يكون جميع ما قالوه خطأ حتى يرد عليهم هذا لو انفردوا بذلك عن الأمة فكيف وقد وافقوا في قولهم
Indeed the Fuqaha of Imamiyyah from their first ones to the last ones who cites from AhleBayt that the Talaq sworn upon doesnt occur, it is narrated mutawatir to them from Jafar bin Muhammad and others etc from AhleBayt.
And assuming arrogantly that they (Imamiyyah) all lied and said that they all agreed upon in lying when citing from AhleBayt, while their group includes Fuqaha, People of Knowledge and Great insight in ijtihad, even though they are mistaken innovators in the matter of Companions of Prophet of Allah [pbuh] , but it doesn’t necessitates ruling all of them to be of lying and ignorance, thus the Authors of Sahihain have taken their hadith, carried their Narrations, took Evidence from them, the Fuqaha didn’t cease citing their difference of opinions and discussing them. A group even though mistaken in some places doesnt mean all of their positions are mistaken upto the extent they are rejected, this is when they are alone in that opinion from rest of the Ummah, then how about if they are in accordance with them.
