This means that Ali had been the vicegerent of the prophet...
This means that Ali had been the vicegerent of the prophet from the start of prophethood to its end. The fact that this hadith has been narrated by the prophet at several occasions further proves that Ali is the only one who can take over the responsibilites of the prophet while alife and after his demise.
The Quran states the following verses: Quran 20:29-36 (29) "And give me a Minister from my family, (30) "Aaron, my brother; (31) "Add to my strength through him, (32) "And make him share my task: (33) "That we may celebrate Thy praise without stint, (34) "And remember Thee without stint: (35) "For Thou art He that (ever) regardeth us." (36) (Allah) said: "Granted is thy prayer, O Moses!" وَاج'عَل لِّي وَزِيرًا مِّن' أَه'لِي {29} هَارُونَ أَخِي {30} اش'دُد' بِهِ أَز'رِي {31}وَأَش'رِك'هُ فِي أَم'رِي {32} كَي' نُسَبِّحَكَ كَثِيراً {33} وَنَذ'كُرَكَ كَثِيراً {34} إِنَّكَ كُنتَ بِنَا بَصِيرًا {35} قَالَ قَد' أُوتِيتَ سُؤ'لَكَ يَا مُوسَى {36} Quran 25:35 (Before this,) We sent Moses The Book, and appointed his brother Aaron with him as minister;وَلَقَد' آتَي'نَا مُوسَى ال'كِتَابَ وَجَعَل'نَا مَعَهُ أَخَاهُ هَارُونَ وَزِيرًا Quran 7:142 And We appointed with Musa a time of thirty nights and completed them with ten (more), so the appointed time of his Lord was complete forty nights, and Musa said to his brother Haroun: Take my place among my people, and act well and do not follow the way of the mischief-makers.
وَوَاعَد'نَا مُوسَى ثَلاَثِينَ لَي'لَةً وَأَت'مَم'نَاهَا بِعَش'رٍ فَتَمَّ مِيقَاتُ رَبِّهِ أَر'بَعِينَ لَي'لَةً وَقَالَ مُوسَى لأَخِيهِ هَارُونَ اخ'لُف'نِي فِي قَو'مِي وَأَص'لِح' وَلاَ تَتَّبِع' سَبِيلَ ال'مُف'سِدِينَ It is therefore clear that Harun was the only one to take over the responsibilities of Moses during his absence and in the event of the demise of Moses, Harun would have become his successor.
This hadith has been narrated on the authority of Shu'ba with the same chain of transmitters. Amir b. Sa'd b. Abi Waqqas reported on the authority of his father that Muawiya b.
Abi Sufyin appointed Sa'd as the Governor and said: What prevents you from abusing Abu Turab (Hadrat 'Ali), whereupon he said: It is because of three things which I remember Allah's Messenger (may peace be upon him) having said about him that I would not abuse him and even if I find one of those three things for me, it would be more dear to me than the red camel.