Does the hadith 'You are to me as Aaron was to Moses' designate Ali as successor?

In the third chapter of Minhaj al-Sunna – the chapter on the proofs that Ibn al-Mutahhar al-Hilli gave in Minhaj al-Karama for the imamate of Ali after the Prophet ﷺ – the hadith of the rank, "You are to me as Aaron was to Moses", comes as the third of his hadith proofs, after the hadith of Ghadir treated in the card on Ghadir. This card gives Ibn Taymiyya's answer first, then al-Hilli's argument as Ibn Taymiyya quotes it, and does not decide between them. ^{1 2}

Ibn Taymiyya quotes al-Hilli: the exception "except that there is no prophet after me" shows that the Prophet gave Ali all the ranks of Aaron with Moses; one of Aaron's ranks was being Moses' deputy, and had he outlived Moses he would have been his successor too – otherwise he would have been demoted; and since the Prophet appointed Ali while present and for a short absence, all the more so after his death and the long absence. ² Al-Hilli's fourth proof follows, as Ibn Taymiyya quotes it: the Prophet appointed Ali over Medina for a short absence, so he must be his successor after death; he never removed him, so he remained deputy there; and being deputy there he was deputy elsewhere. ³

Ibn Taymiyya grants that the hadith "is established in the two Sahihs beyond doubt" and says the Prophet said it to Ali during the Tabuk campaign. He notes that the Prophet never left Medina on a campaign, umra or pilgrimage without appointing one of the Companions over it, and lists examples which the editor documents from the sira works: Uthman in the campaign of Dhu Amarr, Bashir ibn Abd al-Mundhir, and Ibn Umm Maktum. ^{2 4} Tabuk, he says, was the Prophet's last campaign, and no one was allowed to stay behind, so only women, children, the excused and the hypocrites remained in Medina; this appointment was therefore "weaker than the usual appointments", which is why Ali came out weeping: "Are you leaving me behind with the women and children?" ⁴ He mentions a report that some hypocrites slandered Ali, saying he was left behind because the Prophet disliked him, and the Prophet showed him that being made deputy implies honour and trustworthiness, since Moses did it with Aaron. He distinguishes the two cases: the army stayed with Aaron while Moses went alone, whereas at Tabuk the whole army went with the Prophet. ⁵

Ibn Taymiyya argues that "this one is in the rank of that one" is a comparison that holds as far as the context indicates. He cites the hadith of the Badr captives in the two Sahihs, where the Prophet likened Abu Bakr to Abraham and Jesus and Umar to Noah and Moses – a greater comparison than Ali's with Aaron, since those prophets are greater than Aaron – without meaning that they were like them in everything, only in gentleness and severity for God's sake. ^{5 6} Singling out Ali by name, he adds, is an "implication from a proper name" (mafhum al-laqab), which most legal theorists do not accept as evidence, and Ali was named for a reason – he had come out weeping; he gives other hadiths where someone was named for a particular reason, as when the Prophet said of Hatib that he had fought at Badr, and of Urwa ibn Mas'ud that he was like the man of Ya-Sin. ^{6 7} The words "Are you not content to be to me as Aaron was to Moses?" show, for him, that the Prophet was consoling and reassuring Ali, not granting him all of Aaron's ranks. ⁸

• After returning from Tabuk the Prophet sent Abu Bakr as leader of the pilgrimage and sent Ali after him; Ali was with him "like one under command with his commander". He was sent to repudiate the treaties with the Arabs, since by their custom only a chief or a man of his household could make or annul a treaty; the editor documents the report from al-Bukhari and others. ^{8 9}
• Had the Prophet meant succession, he would have stated it to everyone in clear words, not as a private exchange after Ali came out complaining; and had Ali known he was the appointed successor, he would not have come out weeping. ⁹
• The Prophet appointed someone other than Ali over Medina in the year of Khaybar while Ali was there, and someone else again after Tabuk, at the Farewell Pilgrimage; if appointments were presumed to continue, the last one would have the better claim. ^{9 10}

Ibn Taymiyya distinguishes the two: deputising in life is a kind of delegation every ruler needs, and the deputy acts like an agent on his principal's orders; the Prophet appointed in his lifetime men who were not fit to succeed him. Succession after death is independent authority exercised according to the common good, and the Prophet after his death bears no further charge, having conveyed his message. ^{10 3} Answering the fourth proof, he says that if the established hadiths indicate anyone's appointment after the Prophet's death, they indicate Abu Bakr's (see the card on Abu Bakr), and he faults the Imamis for rejecting analogy while here arguing by analogy from deputising during an absence to succession after death. ¹¹

Ibn Taymiyya holds that the appointments over Medina are not peculiar to Ali and indicate neither superiority nor imamate; Ali's established merits are "shared", and their benefit is to establish his faith and standing as a friend of God "and to refute the Nawasib who revile him, call him sinful or call him an unbeliever", as the merits of the first three caliphs refute the Rafida. He compares turning shared merits into Ali's exclusive ones to what the Christians did with the miracles of Christ. These are his judgements in the course of his polemic, including his description of his opponents as ignorant. ^{10 3}

Al-Hilli's own text from Minhaj al-Karama, the Imami commentaries on the hadith from their own sources, and the wordings and chains of the hadith taken directly from the two Sahihs have not yet been added.