Narrated Sa'd bin Abi Waqqas:
that the Prophet (ﷺ) said to 'Ali, "You are to me, in the position that Harun was to Musa, [except that there is no Prophet after me]." (IT)
English reference (IT): Vol. 1, Book 46, Hadith 3730 (IT)
Arabic reference (IT): Book 49, Hadith 4096 (IT)