It was not only at Ghadir Khumm that the Messenger of God, peace and blessings be upon him and his family, proclaimed 'Ali, peace be upon him, to be the leader of the Muslims and his successor, officially and in the presence of the people. In the third year of his mission, when he was commanded to proclaim his prophethood openly, he appointed 'Ali, peace be upon him, as his successor. It is known that for the first three years of his prophetic mission, the Most Noble Messenger, peace and blessings be upon him and his family, did not make his summons public, instead calling people to Islam in secret. It was in the third year of his mission that he was instructed to invite his relatives to Islam openly. 
He thereupon instructed 'Ali, peace be upon him, to invite forty of the leading personages of Quraysh to a banquet, and forty of the Prophet's relatives accepted.
At their very first session, the nonsensical ravings of Abu Lahab, his raging anger and unbridled arrogance, caused the meeting to break up in confusion. The following day, when again everyone was gathered in accordance with the instructions of the Most Noble Messenger, peace and blessings be upon him and his family, first food was served to the guests, and then it was time for spiritual nourishment. The Prophet, peace and blessings be upon him and his family, stood up among his relatives, praised and supplicated the Creator, and said:
"I swear that there is none worthy of worship other than the One God, and that I am His envoy to you and the entirety of mankind. I have brought you the means of felicity in both worlds. My Lord has commanded me to summon you to the religion of Islam, and I give you glad tidings that whoever among you accepts my summons the soonest and aids me in my mission will be my brother (akhi), my legatee (wasiyyi) and my successor (khalifati)."
Those words greatly disturbed those present at the gathering, for their pride was offended, and it almost seemed that the voice of truth and the summons of prophethood would remain unheeded. Suddenly 'Ali b. Abi Talib, peace be upon him, arose and cried out: "O Muhammad, I believe in the oneness of God and your messengerhood and I distance myself from the idol worshippers."
The Prophet, peace and blessings be upon him and his family, ordered 'Ali, peace be upon him, to sit down. He then repeated twice more his earlier proclamation, but those words of truth made no impact on the hearts of those gathered in that assembly. No one apart from 'Ali, peace be upon him, responded to the call of the Prophet, peace and blessings be upon him and his family. ''Ali's acceptance of that summons and his declaration of agreement with the Prophet, peace and blessings be upon him and his family, came at a time when he was just entering manhood. While everyone else sat voiceless and silent, he arose courageously and affirmed his acceptance of the Prophet's call a second time. Thereupon the Prophet turned to the assembly and said: "'Ali is my brother and legatee and my successor among you. Obey him, follow him, and pay heed to his words." 
The reaction of the assembled guests was extremely hostile, for they wished to strip this declaration by the Prophet, peace and blessings be upon him and his family, of its effect, and they therefore stood up and quit the meeting in the most unworthy and discourteous fashion. This event constitutes one of the plainest and most significant chapters in history, and none of the well known historians has ever seen fit to deny its occurrence, Not even the most narrow-minded among them have been able to excise this historic occurrence from their writings.
At that delicate and dangerous juncture, when the Prophet, peace and blessings be upon him and his family, found himself alone in pursuing his great and glorious goal, he needed a helper and ally capable of supporting him powerfully and historically. Such a person could only be one who was prepared to devote himself fully to the Prophet, peace and blessings be upon him and his family, and who had attained the highest degree of sincerity, courage, and obedience to God, so that once he came to exercise the office of successor, he would be a mirror reflecting all the knowledge, wisdom and moral purity of the Prophet, peace and blessings be upon him and his family.
The Prophet, peace and blessings be upon him and his family, knew that although some of his relatives might accept his call and come to embrace Islam, none among them would be prepared to commit himself to active collaboration or to confront the various forces arrayed against him, the idolators of Arabia and the People of the Book. Such a commitment would necessarily involve a protracted and merciless struggle against all sectors of Arab society, for none of them was prepared to tolerate the summons to change their beliefs and abandon their idols. The suggestion that they should do so could not fall to arouse their intense hostility, so that a conflict was completely inevitable, a conflict that would lead to the destruction of the possessions of anyone who allied himself with the Prophet, peace and blessings be upon him and his family.
Someone who was ready to make himself a protective shield for the Prophet, peace and blessings be upon him and his family, under those unfavorable conditions and even to risk him own life had to be an extraordinary individual. Without doubt there was none among the relatives of the Prophet, peace and blessings be upon him and his family, who possessed the necessary qualities apart from 'Ali, peace be upon him, who was indeed destined to demonstrate in the bitter and punishing events that were to occur extraordinary and even unique qualities of heroism and devotion.
The significance of the proclamation made by the Messenger of God, peace and blessings be upon him and his family, on that day is thus clear. It permits us to understand why he undertook to name as his successor and legatee the one and only person who promised him full collaboration.
Taking into consideration the Qur'anic verse, "The Prophet says nothing out of mere fancy, and whatever he utters is the fruit of revelation from his Lord,"(53:3-4) we must conclude that on that very day, during the earliest part of his mission the Prophet, peace and blessings be upon him and his family, clearly and unmistakably appointed 'Ali, peace be upon him, to be leader and guide of the people after his death.
The traditions in which this occurrence is recorded furthermore indicate that the question of succession was the direct prerogative of God and the Messenger, peace and blessings be upon him and his family, and that the people cannot resolve so momentous a matter in accordance with their own wishes. Indeed, the question was of such significance that the Imamate was proclaimed together with prophethood on one and the same occasion, in a gathering attended by the foremost relatives of the Prophet, peace and blessings be upon him and his family.
Ibn Hisham, the well known historian, writes: "Ali b. Abi Talib was the first man to believe in the Prophet, peace and blessings be upon him and his family, to pray together with him, and to affirm the veracity of that which God gave him, although on that day he was a ten year old child." 
Anas b. Malik remarks: "The Prophet began his mission on Monday, and 'Ali embraced Islam on Tuesday." 
Ibn Majah in his al-Sunan and al-Hakim in his al-Mustadrak record 'Ali, peace be upon him, to have said: "I am the servant of God and the brother of His Messenger. I am the supremely veracious one, and none but a liar shall say the same after me. I made the prayer seven years before anyone else did." 
The Most Noble Messenger, peace and blessings be upon him and his family, emphasized on various occasions that the question of leadership of the ummah pertained to God alone, and that he played no role in this respect.
al-Tabari records the following in his history: "A tribal chief by the name of al-Akhnas made his allegiance and obedience to the Prophet, peace and blessings be upon him and his family, conditional on the leadership of the ummah being assigned to him after the death of the Prophet The Prophet, peace and blessings be upon him and his family, responded: 'This is a matter that belongs to God; He will appoint to this office whomever He deems fit' The chief in question was disappointed and he sent a message to the Prophet, peace and blessings be upon him and his family, saying that it was unacceptable that he should toil and exert himself only to see the leadership go elsewhere." 
Can it then be permissible to prefer a leader chosen by the people to the one selected by God and His Messenger, or to place that lofty personage under the authority of someone else, obliging him to obey him and follow his command? The Qur'an clearly proclaims: "None has free choice when confronted with the command of God and His Messenger. Whosoever disobeys the command of God and His Messenger falls prey to obvious misguidance." (33:34)
When, therefore, God selects a certain person to be the guide and leader of the people, that person is the caliph." even if the Muslim community does not make it possible for him to exercise governmental authority. It is the same as in., the case of prophethood: if God appoints a person as prophet, that person is a prophet, even if people do not believe in him and refuse to obey him.
Another precious utterance in which the Messenger of God, peace and blessings be upon him and his family, emphasizes to the Islamic ummah that 'Ali, peace be upon him, is their leader and ruler is the hadith known as the "hadith of the Rank" (hadith al-manzilah). The circumstances under which it arose are the following: One day the Prophet, peace and blessings be upon him and his family, learned that the armies of Byzantium were mobilizing for an attack on Madinah in the hope of gaining a swift victory. Upon hearing this, he ordered precautions to be taken and with a single order he was able to assemble a large force of Muslims to confront the enemy.
At the same time, a report reached the Prophet, peace and blessings be upon him and his family, that the Hypocrites were also gathering their forces with the aim of causing disorder in the city during the anticipated absence of the Prophet, peace and blessings be upon him and his family, by killing and inciting people to violence.
The Most Noble Messenger, peace and blessings be upon him and his family, appointed 'Ali, peace be upon him, to guard the city on his behalf, and he ordered that he should remain in Madinah until he returned, administering the affairs of the Muslims. When the Hypocrites realized that their treacherous plans had been divulged, they began spreading idle rumors in the hope of weakening 'Ali's position. They hinted that the Prophet, peace and blessings be upon him and his family, was angry with 'Ali, peace be upon him, and that it was for this reason that he had not been permitted to accompany him on a major military expedition.
'Ali, peace be upon him, was greatly troubled and saddened by the circulation of these rumors, and he hastened to the presence of the Prophet, peace and blessings be upon him and his family, who had already left Madinah. He told him what had happened, and with a single historic sentence he clarified the special position of 'Ali, peace be upon him, once and for all: "Are you not content that your relation to me shall be like the relation of Harun to Musa, excepting only that there shall be no prophet after me?"
At the end of this hadith there is a sentence that many Sunni scholars have recorded in their books: "It is not fitting that I should depart without your being my deputy and successor." 
Sa'd b. Abi Waqqas, who was an obstinate enemy of 'Ali peace be upon him, mentions the same hadith in order to demonstrate his high standing.
When Mu'awiyah wanted to have the people of Makkah swear allegiance to Yazid, he convened an assembly of some of the Companions at the place known as al-Nadwah. He began by condemning and criticizing 'Ali, peace be upon him, expecting Sa'd to agree with him at least on this point. But contrary to his expectations, Sa'd turned to Mu'awiyah and said: "Whenever I recall three luminous moments in the life of 'Ali, peace be upon him, I wish from the bottom of my heart that they had been mine. The first of the three came on that day when the Messenger of God, peace and blessings be upon him and his family, said to 'Ali, peace be upon him, 'Your relation to me shall be like the relation of Harun to Musa, excepting only that there shall be no prophet after me.'
"The second came on the plain of Khaybar when the Prophet, peace and blessings be upon him and his family, said: 'Tomorrow I will entrust the banner to one who loves God and His Prophet and whom God and His Prophet love. He will be the conqueror of Khaybar, for he never turns his back on the enemy.'
"The third was on the day when the Prophet, peace and blessings be upon him and his family, disputed with the Christians of Najran. He gathered 'Ali, Fatimah, Hasan and Husayn, peace be upon them all, around him, and presented them to the divine presence, saying, 'O Lord, these are the people of my house.'" 
In the hadith comparing his relation with 'Ali to that of Musa (Moses) with Harun (Aaron), the Prophet, peace and blessings be upon him and his family, had implicitly designated 'Ali as his brother, assistant and general deputy as well as leader of the ummah, and the fact that he excepted only prophethood indicates the comprehensive nature of the station he awarded to 'Ali, peace be upon him.
If we refer to the Qur'an, we will see that God Almighty granted all the requests Musa made on him, and it was in accordance with one such request that He appointed Harun the helper, assistant, deputy and successor of Musa among his people, and even made him a prophet.  Since Harun was the leader of all the Bani Isra'il, the situation of 'Ali, peace be upon him, was analogous. Just like the Most Noble Messenger, peace and blessings be upon him and his family, he was the ruler of all the Muslims, and his acting on his behalf as his deputy when he was not present was therefore entirely natural, a consequence of his comprehensive deputyship. Likewise, the deputyship exercized by Harun when Musa went to the place of assignation was not temporary in nature.
Someone might be of the view that 'Ali's deputyship was restricted to the period that the Prophet, peace and blessings be upon him and his family, was absent from Madinah, so that the hadith under discussion cannot be taken as having general significance or as evidence that he was the Prophet's successor.
To this we answer that whenever the Prophet, peace and blessings be upon him and his family, left the Islamic capital, he would always appoint someone to act as his deputy. If by comparing 'Ali, peace be upon him, to Harun, the Prophet, peace and blessings be upon him and his family, had intended nothing more than the usual appointment of a deputy, restricted in his authority to Madinah for the period of the Prophet's absence, why did he not use a similar expression for those other favored Companions he would appoint as deputy? Why did he not use the same or similar words to describe the services they rendered?
History provides no evidence that the Prophet, peace and blessings be upon him and his family, uttered these words with respect to anyone but 'Ali, peace be upon him. The simple truth of the matter is that the Prophet, peace and blessings be upon him and his family, made use of the occasion to proclaim the virtues of 'Ali, to appoint him as his successor, and to make plain that he was his sole legatee. If the Prophet had intended to appoint him only as his deputy for a limited time, it would have made no sense for prophethood to be excluded from the prerogatives of his office. The meaning then would have been something improbable like the following: "'Ali, stand ill as my deputy for a while until I return, but you will not be a prophet after me." The exception made of prophethood makes sense only if the various powers and attributes of Harun should continue to pertain to 'Ali after the death of the Prophet.
Moreover, this expression was used by the Prophet in appointing 'Ali as his successor on other occasions as well, not simply when assigning him deputyship in Madinah, as history bears witness. For example, in the earliest days of the Hijrah, when the Prophet caused every Muslim to conclude a pact of brotherhood with another Muslim, 'Ali hastened sorrowfully to the presence of the Prophet and said: "How is it that you have assigned every Muslim a brother, but have not chosen anyone to be my brother?" In the presence of a group of Companions, the Prophet then replied: "I swear by the Lord Who sent me with the message of truth, I delayed the matter only in order to make you my brother. You are to me as Harun was to Musa, excepting only that there shall be no prophet after me. You are my heir and my brother. " 
This hadith demonstrates among other things that the barring of 'Ali from prophethood was not because of any unfitness on his part, but only to the fact that Muhnammad, peace and blessings be upon him and his family, was the Seal of the Prophets. Had prophethood not been sealed with him, 'Ali would doubtless have been a prophet.
The Messenger of God, peace and blessings be upon him and his family, called 'Ali, peace be upon him, his brother on a number of occasions.
Thus we read in the Sirah of al-Halabi: "After the Prophet concluded pacts of brotherhood among the Companions (for example between Abu Bakr and 'Umar, Usayd b. Hudayr and Zayd b. al-Harithah, Abd al-Rahman bn 'Awf and Sa'd b. al-Rabi', and Abu 'Ubaydah and Sa'd b. Mu'adh), he took 'Ali by the hand and proclaimed, 'This is my brother.' Thereafter 'Ali and the Messenger of God were brothers." 
On another occasion, when discussing a matter that concerned 'Ali, his brother Ja'far, and Zayd b. al-Harithah, the Prophet addressed ''Ali as follows: "As for you, O 'Ali, you are my brother and comrade." 
On yet another occasion he said: "You will be my brother and companion in Paradise." 
Let us now see what is meant by brotherhood in this context.
In order to abolish and obliterate all forms of tribal distinction and privilege which were contrary to the norms of divine justice, the Prophet undertook a number of necessary measures, above all by establishing a special type of brotherhood among the Muslims after the migration to Madinah. It was his wish to bring a comprehensive brotherhood into being in the Islamic ummah, not as an abstract idea but as a palpable and objective reality. By the coming together of two adoptive brothers, who were not linked by any ties of blood or kinship but only by closeness to God and belief in the truths of His religion, the new brotherhood of Islam began to blossom in a practical form. Spiritual brotherhood became the equivalent of genealogical kinship. The links between two adoptive brothers, each hailing from a different tribe and town, contributed moreover to a general expansion of friendship and affection between all the members of the two different tribes, so that a network of deep spiritual and emotional links came into being.
The brotherhood of the Most Noble Prophet, peace and blessings be upon him and his family, and 'Ali, peace be upon him, had come into being no less than ten years before the Hijrah, when the Prophet convened a gathering of his relatives at his house in order to request their aid. The Prophet's purpose in establishing this fraternal link with 'Ali was without any doubt different from the goal of creating closeness between two tribes or the people of two cities that he pursued in Madinah, not least because no such gap or difference separated him from 'Ali. They were already related to each other as cousins and firm, strong ties already existed between them.
The reason for the brotherhood between the Prophet and 'Ali must therefore have been spiritual and intellectual affinity, a mutual inward attraction. It was 'Ali who more than anyone else resembled the great founder of Islam with respect to his spiritual qualities and knowledge, his devotion and insight. The brotherhood of the Prophet with 'Ali had therefore a special significance that extended beyond this world to the plain of resurrection and the realm of the hereafter. Thus al-Hakim records in his al-Mustadrak the following remark addressed to 'Ali by the Messenger of God, handed down by two separate authentic chains of transmission: "You are my brother in this world and the hereafter." 
One day when Abu Bakr, 'Umar and Abu 'Ubaydah were present, the Prophet placed his hand on the shoulder of 'Ali and said: "O 'Ali, you are the first person who accepted Islam and believed in me; you are to me as Harun was to Musa." 
Once 'Umar saw a man insulting 'Ali b. Abi Talib. 'Umar told him: "You are a hypocrite, for I heard the Messenger of God say to 'Ali, 'Only 'Ali is to me as Harun was to Musa, excepting only that there shall be no prophet after me."' 
A point to be noted in this tradition is that since the Arabic particle innama (only) implies exclusivity, the Prophet cannot have meant 'Ali's deputyship to be temporary, for he also appointed others as his deputies from time to time. 'Umar's words also imply that he understood the Prophet's declaration to make 'Ali his equal in all respects except prophethood, for he told the man who insulted 'Ali, "You are a hypocrite." His hypocrisy was indeed worse than open unbelief.
However high be the rank of a believer, to insult him entails neither unbelief nor hypocrisy. 'Umar and many of the Companions used to insult each other, but no one ever interpreted this kind of behavior as entailing unbelief or hypocrisy. However, insulting the Prophet, peace and blessings be upon him and his family, does indeed entail unbelief, and it can therefore be said that 'Umar b. al-Khattab understood the words of the Prophet to mean that 'Ali, peace be upon him, had the same rank as the Prophet himself.
The hadith of the Ark (hadith al-safinah) is one more of the well-known and universally accepted traditions found in the books of celebrated Sunni scholars that establish the worthiness of the Prophet's family for assuming the leadership and direction of the Islamic ummah, Abu Dharr al-Ghifari relates the Prophet to have said: "The People of my Household are for you like the Ark of Nuh (Noah). Whoever embarks on it will be saved and whoever turns away from it will be drowned." 
With these words the Prophet depicts clearly the rank of his family and their fundamental role in guiding mankind and giving direction to the Islamic ummah. He warns against the perilous consequences of abondoning the lofty and salvific persons of his house, a course that will lead whoever chooses it to darkness and misguidance.
The sense of comparing the People of the House (Ahl al-Bayt) to the Ark of Nuh is that whoever follows their guidelines in fulfilling his religious duties and whose acts conforms to their commands is guaranteed salvation from the awesome punishment that awaits on the Day of Judgement Whoever rebels and disobeys, who distances himself from that axis of orientation, is like the one who sought refuge from the dreadful tempest on the mountaintops instead of in the Ark of Nuh. The only difference is that the latter met his death by drowning, while the former will be submerged in the torment of hellfire and eternal perdition.
The Most Noble Messenger, peace and blessings be upon him and his family, said in description of the People of his House: "The People of my House are like the stars that help men find their way on sea and dry land and deliver them from misguidance and errance." 
He said further. "Whoever seeks refuge with the People of my House will be safe from misguidance and ruin, and whoever opposes them will fall prey to discord and divergence and join the party of Satan." 
From the traditions just cited can be deduced also the dimensions of the House, for whoever is exposed to the possibility of committing error and sin, of deviating from the clear guidelines laid down by the Prophet, peace and blessings be upon him and his family, will never be able to save others from falling into the pit of misery and misguidance or to bring about that radical change in modes of thought, feeling and social organization that is needed to ensure eternal felicity.
It would be possible to object against the Shi'ah or to condemn them for the path they have elected only if their obedience to the People of the Prophet's House were inspired by something other than his instructions and recommendations. Such, however, is not the case.
When the first caliph appointed the second caliph as his successor, what word or sentence did he use? Did he use more than one sentence to indicate that the office of caliphate and leadership of the Muslims that he had exercised now fell to the lot of 'Umar? By contrast, there are numerous expressions and sentences from the Prophet, clear and explicit in meaning, concerning 'Ali; do they not suffice to prove his leadership and succession? The words of the Prophet are far clearer and more explicit than those used by the first caliph; are they not enough to prove at least the claim of 'Ali to religious leadership? Fair-minded and intelligent people can judge for themselves.
The scholars and leading figures of the Sunni community have regarded it as necessary to follow the views and teachings of the founders of the four schools of Sunni law, even though there is no hadith from the Messenger of God, peace and blessings be upon him and his family, enjoining such obedience. We can therefore discern no adequate reason for these same scholars to ignore the teachings of the People of the Prophet's House, in the face of his clear declaration that the Our'an and the People of the House will remain inextricably linked until the Day of Judgement. 
What is even more remarkable is that some of the founders of the four legal schools were themselves students of the People of the House and benefited from their erudition. A leading Sunni scholar remarks: "All Islamic scholars, irrespective of the school to which they belong, are unanimously agreed on the accomplishments and learning of Imam al-Sadiq, peace be upon him. Sunni Imams who were his contemporaries studied with him and derived knowledge from him. Malik learned from him, as did some of the contemporaries of Malik such as Sufyan b.
Uyaynah, Sufyan al-Thawri, and many others. Abu Hanifah, whose lifetime more or less corresponded to that of Imam al-Sadiq, peace be upon him, studied religious knowledge with him and regarded him as the most learned man of the age." 
Ibn Hajar, another Sunni scholar, relates Imam al-Shafi'i to have said: "The Household of the Prophet is my means of salvation, and they are my means of drawing near to the Prophet. It is my hope that for their sake the record of my deeds will be given into my right hand on the Day of Judgement." 
Again al-Shafi'i said: "O People of the Prophet's House, love for you has been made obligatory by God through mention in the Qur'an. Sufficient cause of pride it is for you that whoever fails to invoke blessings on you in his prayer will fail to have his devotions (salat) accepted." 
Unlike the views of the mujtahids who founded the four Sunni schools, there is no contradiction or divergence among the teachings of the People of the House, for they were not engaged in independent reasoning on the ordinances of religion. Their teachings are identical with those of the Prophet, peace and blessings be upon him and his family, of which the Imams of the People of the House were infallibly aware. The utterances of the Imams cannot therefore be placed on the same level as the views of the founders of the four Sunni schools.
In view of all this, how can it be justified to ignore and neglect the teachings of the People of the House?
 Ahmad b. Hanbal, al-Musnad, Vol. I, pp. 111, 159. Ibn al-Athir, al-Kamil, Vol. II, p.22; al-Tabari, al-Tafsir, Vol. II, p. 216; Abu al-Fida', al-Tarikh, Vol. I, p. 119; al-Ganji, Kifayatal-Talib, p.89. al-Nasa'i, al-Khasa'is, p. 18; al-Halabi, al-Sirah, Vol. I, p.304; Ibn Abi 'l-Hadid, Sharh, Vol. III, p. 255; al-Suyuti, Jam' al-Jawami', Vol. VI, p. 408; al-Khifaji, Sharh al-Shifa', Vol. III, p. 37.
 Ibn Hisham, al-Sirah, Vol. I, p.245.
 al-Hakim, al-Mustadrak, Vol. III, p. 312.
 Ibn Majah, al-Sunan, Vol. I, p. 44; al-Hakim, al-Mustadrak, Vol. III, p. 112.
 al-Tabari, Tarikh, Vol. II, p. 172.
 al-Bukhari, al-Sahih, Vol. III, p.58; Muslim, al-Sahih, Vol. II, p. 323; Ibn M'ajah, al-Sunan, Vol. I, p. 28; al-Hakim, al-Mustadrak, Vol. III, p. 190; Ibn Hajar, Sawa'iq, p. 30; al-Muttaqi al-Hindi, Kanz al-'Ummal, Vol. VI, p. 152; al-Qunduzi, Yanabi' al-Mawaddah, p. 240; al-Nasa'i, al-Khasa'is ., p.7; Ibn Sa'd, al-Tabaqat, Vol. III, p.24.
 al-Hakim, al-Mustadrak, Vol. III, p. 63; al-Nasa'i, al-Khasa'is ., p. 63; al-Hamawini, Fara'id al-simtayn, Vol. I, p. 328 al-Dhahabi, Talkhis al-Mustadrak, Vol. III, p. 132; Ahmad b. Hanbal, al-Musnad, Vol. I, p. 331; al-Khwarazmi, al-Manaqib, p. 72; al-Ganji, Kifayat al-Talib, p. 116; Ibn Asakir, al-Tarikh al-Kabir, Vol. I, p. 203; al-Biladhuri, Ansab al-Ashraf, Vol. II, p. 106; Ibn Kathir, al-Bidayah, Vol. VII, p. 338; al-'Asqalani, al-Isabah, Vol. II, p.509.
 Muslim, al-Sahih, Vol. VII, p. 120; Ibn 'Asakir, al-Tarikh al-Kabir, Vol. I, p. 334; Ibn Kathir, al-Bidayah, Vol. VII, p. 341; al-Muttaqi al-Hindi, Kanz al-'Ummal, Vol. XIII, p. 163; Ibn Majah, al-Sunan, Vol. I, p.58; al-Nasa'i, al-Khasa'is, p.50; al-Qunduzi, Yanabi' al-Mawaddah, p. 51.
 See Qur'an, 20:29-32.
 al-Muttaqi al-Hindi, Kanz al-'Ummal, Vol. V, p.31.
 al-Halabi, al-Sirah, Vol. II, p. 97. Ibn Hisham, al-Sirah, Vol. I, p.505.
 Ibn Sa'd, al-Tabaqat, Vol. VIII, p. 114.
 Ibn 'Abd al-Barr, al-Isti'ab, Vol. II, p. 460; al-Khatib al-Baghdadi, Tarikh Baghdadi, Vol. XII, p. 268; al-Firuzabadi, Fada'il al-Khhamsah, Vol. I, p.114.
 al-Hakim, al-Mustadrak, Vol. III, p. 414; al-Tirmidhi, Jami' al-Sahih, Vol. V
 al-Muttaqi al-Hindi, Kanz al-'Ummal, Vol. VI, p. 395.
 Ibn , Asakir, al-Tarikh al-Kabir, Vol. I, pp. 360-61; al-Khatib al-Baghdadi, Tarikh Baghdad, Vol. VII, p.453.
 al-Muttaqi al-Hindi, Kanz al-'Ummal, Vol. I, p. 250; Ibn Hajar, al-Sawa'iq, p. 75; al-Hakim, al-Mustadrak, Vol. III, p. 343; al-Qunduzi, Yanabi' al-Mawaddah, p. 257. Ibn al-Sabbagh, al-Fusul al-Muhimmah, p. 10; al-Sabban, Is'af al-Raghibin, p. 111; al-Shiblanji, Nur al-Absar, p. 114.
 Ibn Hajar, al-Sawa'iq, p. 140; al-Hakim, al-Mustadrak, Vol. III, p. 149.
 Ibn Hajar, al-Sawa'iq, p. 140; al-Hakim, al-Mustadrak, Vol. III, p. 149.
 Ahmad b. Hanbal, al-Musnad, Vol. V, p. 181.
 Shaykh Muhammad Abu Zahrah, al-Imam al-Sadiq, p.66.
 Ibn Hajar, al-Sawa'iq, p. 108. See too al-Firuzabadi, Fada'il al-Khamsah, Vol. II, p.81.
 al-Shiblanji, Nur al-Absar, p. 104.
Lessons on Islamic Doctrine, Ayatullah Sayyid Mujtaba Musavi Lari
Translated by: Hamid Algar