Tafsir Al-Askari
He was very knowledgeable and despite being confined to house arrest for almost his entire life, Hasan al-Askari was able to teach others about Islam, and even compiled a commentary on the Qur'an that would be used by later scholars. This became known as Tafsir al-Askari. However, there was many suspicion regarding whether or not it truly was his or not. The Tafsir was accused by some to be weak in its chain of authorities (Sanad), which is an essential part of the transmission of a tradition. The tafsir was also questioned because it contained a few inconstancies and lacks eloquence which some claim ruin its validity by default. The main reason people questioned the validity of the Tafsir is the fact that the Imam was under constant watch by the Abbasid government who prevented any contact between him and the Shi'i so it would make it impossible for such knowledge to be transferred.
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