Reference: Fataawa al-Lajnah ad-Daa.imah lil-Buhooth al-’Ilmiyyah wal-Iftaa – Volume 2, Page 376
Question: What is the ruling regarding the Shee’ah, particularly those who say that ‘Alee [ibn Abee Taalib] is at the level of prophethood, and that [the angel] Jibreel made a mistake in descending upon our [Prophet] Muhammad [(sal-Allaahu ‘alayhi wa sallam) with revelation]?
Response: The Shee’ah are [made up] of many groups, and whoever from amongst them says (believes) that ‘Alee (radhi-yAllaahu ‘anhu) is at the level of prophethood, and that [the angel] Jibreel (‘alayhis-salaam) made a mistake in descending upon our Prophet Muhammad (sal-Allaahu ‘alayhi wa sallam) – then he is a disbeliever.
And with Allaah lies all the success, and may Allaah send prayers and salutations upon our Prophet Muhammad (sal-Allaahu ‘alayhi wa sallam) and his family and his companions.