Hadith of Umar's ban on hadith decision of Muhammad was rescinded later in his ministry. During Umar's reign as Caliph, hadith were in fact being recorded. On the other hand, some sources dispute this account, and claim that it was Umar himself who was the first person to ban hadith collection - a view also upheld by Shias. Certainly during his rule Umar strictly followed the policy of banning the hadith and he prohibited reporting and transmission of hadith altogether. Whenever he sent a group to a city, he would prohibit them from narrating hadith. This ban continued through the caliphate of the Rashidun caliphs into
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