Hadith are "expressed in Muhammad's words", whereas the latter are the "direct words of God". A "hadith qudsi" need not be a "sahih" (sound hadith), but may be "da‘if" or even "mawdu‘". An example of a "hadith qudsi" is the hadith of Abu Hurairah who said that Muhammad said: When God decreed the Creation He pledged Himself by writing in His book which is laid down with Him: My mercy prevails over My wrath. In the Shia school of thought, there are two fundamental viewpoints of Hadith: The Akhbari view and the Usuli view. The Usuli scholars stress the importance of
Criticism of Hadith According to Racha El Omari, early Mutazilites believed that hadith were susceptible to "abuse as a polemical ideological tool"; that the "matn" (content) of the hadith -- not just the "isnad" -- ought to be scrutinized for doctrine and clarity; that hadith "supported by some form of "tawātur"", i.e. by a large number of "isnād" strands, each beginning with a different Companion, were valid. In writing about "mutawatir" (transmitted via numerous chains of narrators) and "ahad" (any ahadith that is not "mutawatir") and its importance from the legal theoretician's point of view, Wael Hallaq notes the medieval scholar Al-Nawawi argued