Hadith of the two weighty things in Islam as mutawatir and the authenticity of it is confirmed by numerous chains of transmission of Shia and Sunni Muslim . According to Ayatollah Ja'far Sobhani, the hadith points the authoritative knowledge of the Ahl al-Bayt and the Quran and convinces Muslim to believe in both of them together. In spite of difference over historical interpretation, Hadith al-Thaqalayn can improve the union among the Muslims world. According to Sunni tradition (canonical Hadith compiler Muslim b. al-Hajjaj), Hadith al-Thaqalayn was presented by Muhammad prophet at a grove called Khumm. In this tradition Yazid b.Hayyan , Husayn b.Sabrah and Umar b.Muslim
Introduction to the Science of Hadith category, which comprises 21 types, relates to the names of the narrators. This includes the definition of a "ṣaḥābī" (companion), a "tābi`ī" (follower), the time periods of narrators, names and paidonymics among others. Later scholars included additional types of hadith in their own works, with some almost reaching 100. The "Introduction" became the basis for subsequent books in hadith terminology. A number of subsequent scholars followed Ibn al-Ṣalāḥ in the ordering of his book, including al-Nawawī, Ibn Kathīr, al-ʻIraqi, al-Bulqīnī, Ibn al-Jamā`ah, al-Tabrīzī, al-Ṭībī and al-Zirkashī. In many instances this influence was direct, with numerous scholars authoring books indicating its