The Book of Marriage From the Explanation of Bulugh Al-Maraam Part-3
by Shaykh Muhammad Bin Salih Al-Uthaymin
'Ali ibn Abu Talib is the cousin of the Messenger (PBUH), and Fätimah is the daughter of the Messenger (PBUH), the most prestigious lady in Paradise (RA) as stated by the Prophet (PBUH). Additionally, the Prophet (PBUH) said about 'Ali (RA):
"You are in the same position with relation to me as Aaron (Härün) was concerning Moses but with (this explicit difference) that there is no prophet after me."
He said this when he delegated him the responsibility of [Madinah] when Muslims were away in the Tabük conquest. So, he said: O Messenger of Allah! You leave me behind with women and children? To warm his heart, the Prophet (PBUH) said the above narration. It is also because Aaron (Härün) took Musa's place among his people, as he said:
"Replace me among my people." [Sürah 'Al-A'räf (7):142]
The previous 'Ayāt explains the following statement: "You are in the same position with relation to me as Aaron (Harün) was concerning Müsã."
However, as the Prophet (PBUH) feared that anyone would misuse this word and claim that 'Ali is a Prophet like Harun, he said:
"but with (this explicit difference) that there is no prophet after me."
This statement highlights the immense protection the Prophet (PBUH) dedicated to the prestige of the Message [of Islam]. Also, he is concerned about the importance of Tawhid (Islamic Monotheism). Certainly, according to the Qur'an and the Sunnah, it is well-known that he is the last of the Prophets, and there is no Prophet after him.