Hadith of the Quran and Sunnah accept the authenticity of the related Hadith of the two weighty things ("Hadith al-Thaqalayn"). In this hadith, Muhammad referred to the Qur'an and "Ahl al-Bayt" ('people of the house', Muhammed's family) as the two weighty things. Although the hadith is accepted by both Sunnis and Shi'as, the two groups differ on the exact wording of what Muhammad said, as well as how to interpret these words. The Shi'as use the Hadith of the two weighty things to prove their claim that Muhammad meant for all his successors to be from his own family ("Ahl al-Bayt"). The Sunnis reject this view
Introduction to the Science of Hadith adding six terms in the process). The first pertains to the "matn" (text) of the hadith and its three divisions and 30 types. The three divisions are "ṣaḥīḥ", "ḥasan", and "ḍa`īf". The thirty types include those mentioned in hadith terminology and others. The second deals with the "isnād" (chain of narration) and comprises 11 types. These types generally fall within the discipline of biographical evaluation. The third category includes six types: the qualifications necessary for conveying hadith, the manners in which they are transmitted, the transcription of hadith, and the etiquette of the narrator and of the student. The fourth