The commentary of the word of Allah, the High:
طُوبَى لَهُمْ وَحُسْنُ مَآبٍ
“…Tuba shall be theirs and a goodly return” 
In Ghaayah al-Maraam, it is recorded from al-Tha’labi who states, “Informed me Abdullah Ibn Muhammad Ibn Abdullah Ibn Muhammad from Muhammad Ibn Uthman Ibn al-Hasan from Muhammad Ibn al-Husain Ibn Saaleh from Ali Ibn Muhammad al-Dahhaan and al-Husain Ibn Ibraheem al-Jassaas, who both narrate from al-Husain Ibn al-Hakam from Hasan Ibn Husain from Hayyaan from al-Kalbi from Abu Saaleh from Ibn Abbas, who says, ‘Tuba’ (طوبي)implies a tree whose roots are in the house of Ali (a.s.) in Paradise and it has a branch in the house of every believer; it is called as طوبي. And ‘and a goodly return’ means a goodly revisit.
Also, al-Tha’labi records from Abu Saaleh who says “Informed us Abdullah Ibn Sawaad from Jandal Ibn Waaleq al-No’mani from Ismaeel Ibn Umayyah al-Qarashi from Dawood Ibn Abd al-Jabbaar from Jaaber from Imam Abu Ja’far (a.s.) who informs, ‘The Messenger of Allah (s.a.w.a.) was asked about the saying of Allah ‘…Tuba shall be theirs and a goodly return’, he (s.a.w.a.) replied, ‘A tree in Paradise; its root is in my house and its branch is upon the people of Paradise.’ He (s.a.w.a.) was questioned, ‘O Messenger of Allah (s.a.w.a.)! We had enquired from you (earlier) and you said, ‘A tree in Paradise; its root is in the house of Ali and its branch is upon the people of Paradise.’ He (s.a.w.a.) clarified, ‘Surely, my house and Ali’s house is one tomorrow in one place.”
From Muhammad Ibn Seereen concerning the saying of Allah – the High – “Tuba shall be theirs”, he said, “It’s a tree in Paradise. Its root is in the room of Ali and there is no room in Paradise but that in it is a branch from its branches.”
Describing the Tree of Tuba, al-Tha’labi has narrated two traditions:
A) Moaviyah Ibn Qurrah narrates from his father that the Messenger of Allah (s.a.w.a.) said, “Tuba is a tree that Allah – the High – has planted with His own hands, blew in it from His spirit. Jewellery and clothes grow on it. Surely, its branches can be seen from beyond the veils of Paradise.”
B) Andar Ibn Umayr narrates, “It’s a tree in the Garden of Eden. Its root is in the house of the Prophet (s.a.w.a.) and in every house and room, there is a branch from it. Allah has not created a colour except black or flower but that it can be found in it. Allah has not created any fruit but that it is found in it. Two fountains gush out from it: Camphor and Salsabeel. Moqaatel says that through it, every leaf shadows an Ummah; on it is an angel who is glorifying Allah with various kinds of glorifications.
As for the traditions vide our sources, they are truly copious. We shall cite only two traditions for the sake of auspiciousness.
Tradition One: Ibn Baabwayh through his chain of narrators records on the authority of Abu Baseer, who says that Imam Sadeq (a.s.) said, “Tuba is for the one who fastens unto our affair in the occultation of our Qaem and his heart is not deviated after guidance.” I asked him (a.s.), ‘May I be held your ransom, what is Tuba?’ He (a.s.) informed, “It’s a tree in Paradise; its root is in the house of Ali Ibn Abi Taalib (a.s.). There is not a believer but that in his house is a branch from its branches and this is the saying of Allah – Mighty and Majestic be He – ‘…Tuba shall be theirs and a goodly return.’”
Tradition Two: Muhammad Ibn Yaqoob vide his chain of narrators records on the authority of Abu Baseer from Imam Abu Abdillah (a.s.), who says, “Ameerul Momineen (a.s.) said, ‘Surely, for the people of religion there are signs by which they are recognized: Speaking the truth, repaying the trust, fulfillment of covenant, maintaining relations with the kith and kin, having mercy on the weak, not looking at (prohibited) women, generous with goodness, good behaviour, extensive forbearance and following the knowledge in what makes them nearer to Allah, a proximity. Tuba is for them and a goodly return. And Tuba is a tree in Paradise; its root is in the house of the Holy Prophet (s.a.w.a.) and there is not a believer but that in his house is a branch from it. His heart will not feel the desire of a thing but that he can procure the desired thing from this branch. If a fast rider travels in its shadow for a hundred years, he will not come out from it. If a crow flies from its lowest branch, it can never reach to its highest branch till it falls due to old age. Thus, be inclined towards it. A believer is the one who keeps himself busy and the people are in comfort due to him. When night dawns on him, he falls on his face and prostrates before Allah – Mighty and Majestic be He – with the nobility of his body, whispering with the One Who created him about the freedom of his neck. Beware! Then be like this.’”
I say: From the aforementioned traditions, which are abundant in Sunni sources and consecutive in our references, and that explain the noble verse under discussion, it is understood that our master Ameerul Momineen (a.s.) is the chief of the believers, the best of them and the most superior of them after the Holy Prophet (s.a.w.a.). He (a.s.) was to the Holy Prophet (s.a.w.a.) what Prophet Haroon (a.s.) was to Prophet Moosa (a.s.). None is nearer to the Holy Prophet (s.a.w.a.) than him (a.s.) in status and position.
Explanation: His (s.a.w.a.) response to the questioner, “Surely, my house and the house of Ali (a.s.) is one tomorrow in one place” proves that Ali’s (a.s.) position unto the Messenger of Allah (s.a.w.a.) is like that of his (s.a.w.a.) self and both of them will be in one position near Allah – High be His Glory. Like his (s.a.w.a.) saying, “Its root is in the houe of Ali and its branch is upon the people of Paradise; and there is not a believer but that in his house is a branch from it” manifests that he (a.s.) is the most superior of the believers, their chief and the best of them after the Holy Prophet (s.a.w.a.). The first point is also established through the Verse of Malediction (آية المباهلة), the Tradition of Position (حديث المنزلة) and the Tradition of Brotherhood (حديث المواخاة), both of which are consecutively narrated by both the sects. From these, the second meaning also becomes clear because it is necessary that the one, who is of the level of the self of the Holy Prophet (s.a.w.a.) and his (s.a.w.a.) brother, should be the Chief of the Believers, the most superior of them and the best of them.
It is proved especially by the consecutively narrated traditions by both the sects. In Ghaayah al-Maraam, he (r.a.) has mentioned through Sunni sources more than fifty traditions in this context.
From these traditions is what has been narrated from Abu al-Muayyad Muwaffaq Ibn Ahmad – the most eloquent of speakers of Khaarazm and a celebrated Sunni scholar – in his book about the excellences and superiority of Ameerul Momineen (a.s.) through his chains of narrators that end at Anas that the Messenger of Allah (s.a.w.a.) said, “O Anas! Pour water for me for ablution.” Then, he (s.a.w.a.) performed two units of prayers, after which, he (s.a.w.a.) said, “The first to enter upon you through this door will the Chief of the Believers, the Leader of the Muslims, the Guide of the Handsome and the Seal of the Successors.” I was praying secretly, ‘O Allah! Let this person be from the Migrants (Ansaar)’ when Ali (a.s.) came. He (s.a.w.a.) asked, “Who is it, O Anas?” I said, ‘Ali.’ He (s.a.w.a.) stood up happily, embraced him and began wiping the sweat of Ali’s (a.s.) face with his face. Thereafter, Ali (a.s.) said, “O Messenger of Allah! Indeed, I have seen you display so many acts (of affection) with me from before.” He (s.a.w.a.) replied, “And what will stop me from doing these acts when you are the one who will repay on my behalf, listen to my voice and explain for them in what they will dispute after me.”
Explanation: The phrase ‘Seal of the Successors’ implies the seal of the successors of the Prophets (a.s.). It is not contradictory to the fact that he (a.s.) is the first of the successors vis-à-vis to our Prophet (s.a.w.a.). After it has become apparent for you that he (a.s.) is of the level of the self of the Holy Prophet (s.a.w.a.) and that he (a.s.) is the most superior of the believers, their chief and the best of them after the Holy Prophet (s.a.w.a.), it will be clear for you that the distinction of Caliphate and Imamate lies with him (a.s.) because it is impossible that somebody who enjoys such an elevated status and lofty position should be under the allegiance and subjugation of an inferior person from the believers.
 Surah Ra’d (13): Verse 29
 Ghaayah al-Maraam, p. 392 narrating from Tafseer al-Tha’labi
 Ghaayah al-Maraam, p. 392 narrating from Tafseer al-Tha’labi
 Ghaayah al-Maraam, p. 392
 Ghaayah al-Maraam, pp. 391-392 narrating from Tafseer al-Tha’labi
 Ghaayah al-Maraam, p. 392 narrating from al-Saduq (r.a.)
 Al-Kaafi, vol. 2, p. 239; Ghaayah al-Maraam, p. 396
 Ghaayah al-Maraam, pp. 454-460
 Ghaayah al-Maraam, p. 619 narrating from Manaaqeb of al-Khaarazmi, p. 42
 This is in the narration of Muwaffaq Ibn Ahmad. Otherwise, both Shias and Sunnis have narrated on the authority of Anas, ‘Best of the Successors’ instead of ‘Seal of Successors’. Therefore, ‘Seal of the Successors’ appears to be negligence on part of the narrator or the manuscript writer. Even if it’s correct, it should be interpreted according to what we have explained since none has claimed successorship other than him (a.s.). The Sunnis differ on successorship and caliphate. They think successorship to be for Ali (a.s.) and caliphate for Abu Bakr through allegiance. None of them has claimed successorship of the Holy Prophet (s.a.w.a.).