5. The Causes:
In order to understand the underlying cause for al-'Imam al-Rida's (A) acceptance of the fatal allegiance, we must look for the answers on two levels. Firstly, what might have happened if he did not accept, and secondly, what was his aim when he did accept?
Firstly, what might have happened if al-'Imam al-Rida (A) did not accept the fatal allegiance? We believe that which might have happened is as follows:
a. Death. It was necessary for him to avoid being killed, not to preserve his own life, for the Imams did not value their own lives and consider them important except as a means of serving the Ummah. His death would open the door wide for tribulations for the followers of the Ahl al-Bayt (A), who would then have no refuge or guide. We must link the avoidance of death with the essence of the issue of Imamate and its timing, when we note how young al-'Imam al-Jawad (A) was at the time the offer of heir apparency was made. His life was committed to achieving the aims and to avoiding the dangers.
He explained his acceptance to one of his companions who asked him about it, saying: "I chose acceptance over death." To another companion who asked him: "What made you become involved in the (matter of) heir apparency (wilayat al-'ahd)?" he answered: "That which made my grandfather (i.e. 'Ali [A]) to become involved in the council (shura)?"
We must note that he (A) was compelled to give this simple explanation, acceptable to the people, that he being on his guard against being killed, or the ambiguous explanation in which he made al-'Imam 'Ali (A) his precedent. We must also note that he gave explanations of saving himself from being killed in some of his other discussions. However, we must be aware that he was compelled to give this kind of explanation, for he was not in a position to speak openly about the reasons underlying his acceptance, in order not to disclose his plan, the reasons why it was necessary, and his actual objective.
He was under surveillance; his conversations and his letters were controlled. He lived in the same conditions as al-'Imam al-Hasan (A) and bore its agonies, as when he heard someone say to him: "Peace be on you, O humiliator of the believers", without being able to explain his ordeal to the people, not even to many of his confidants. He had to suffer martyrdom every day while he still lived, protecting those whom he loved and defended with his life, while they misunderstood and misinterpreted his actions!
This and other similar situations reveal to us how forlorn the responsibility of leadership was, isolated as he was even from the people closest to him, sad and distressed even in the radiant moments when difficult decisions were taken without being able to explain their reasons. How many agonies and pains did the Imams of the Ahl al-Bayt (A) suffer because of that, especially Amir al-Mu'minin 'Ali ibn Abi Talib (A) who had the greatest share of this kind of suffering!
b. It was possible that he might not have been killed, but even then it was certain that there would be an increase in the repression, persecution and exile of the followers of the Ahl al-Bayt (A). In this way, al-Ma'mun would be able to put pressure on him and take his revenge.
c. It was possible that his rejection of the heir apparency might have led al-Ma'mun's enemies to exploit the situation, which would have added to the stormy revolutionary reactions on the Islamic scene at that time. Moreover, al-Ma'mun's overthrow was in the interests of the hard-line 'Abbasids, the party of al-'Amin, with their attitude to the 'Alids and their hatred of the Iranians; for the followers of the Ahl al-Bayt (A) did not have the ability to take over the government and replace al-Ma'mun after his downfall.
d. It was possible that the refusal might have led to a wide-ranging propaganda against the Imam (A), to the effect that he had let a valuable opportunity pass by, and that in turn might have led to confusion and disarray among the people following the Ahl al-Bayt (A), who would have been subjected to persecution, exile, and intimidation. The inevitable question would have been raised in this dilemma: 'Why didn't he accept when the caliphate was offered to him?', instead of the question:
'Why did he accept?' We may recall circumstances similar to this in the issue of the arbitration after Siffin and that which took place in regard to the issue of the truce (sulh) with al-'Imam al-Hasan (A).
e. Finally, we may ask: Had al-'Imam al-Rida (A) insisted on refusing the offer, wouldn't al-Ma'mun have been able to find an 'Alid substitute, an important member of society, whom he could appoint as successor? There were personalities among the Zaydis who were prepared for such an undertaking. There were also independent 'Alid personalities ready to accept this position. If this occurred, it was certain that the results would have been totally negative, and no new, positive achievements would have been realized by rejecting the offer. This is what such an occurrence could have led to, together with the disagreement that could arise among the followers of the principle of nass.
Secondly, what was his aim when he did accept?
a. It was to avoid all the negative results which would have ensued from his refusal. He had removed the sentence of death on himself, thus avoiding the occurrence of a change in the leadership of the Ahl al-Bayt (A) during a critical period. He had also avoided a new wave of terror, exile and execution against the followers of the Ahl al-Bayt (A), and prevented the hardline 'Abbasid faction from taking full control of the regime. In fact, he had created circumstances suitable for destroying this faction and had neutralized its capacity for political activity and its influence on the course of events.
He had prevented confusion and disorder among the followers of the Ahl al-Bayt (A).
Finally, he had prevented al-Ma'mun from substituting him with 'an 'Alid successor, through whom he could exercise a policy of repression against the followers of the Ahl al-Bayt (A), using the principle of nass as an excuse.
b. By his acceptance, he was able to get in touch with people who would not have dared to communicate with him, had he not been the heir apparent. Thus, there gathered around him the Murji'ites, the Ahl al-Hadith, the Zaydis, the Ahl al-Sunnah and all the Shi'ite sects.
Through this contact, he was able to work with them on the basis of the principle of nass. Through it, he also enabled the traditionists and theologians on the path of the Imams of the Ahl al-Bayt (A) to come into safe and free contact with these opposing sects, and put forward intellectual and political issues for calm, objective, and learned discussion. Al-'Imam al-Rida (A) himself practised this kind of wide-flinging intellectual activity. We should not underestimate the positive intellectual and political results which were achieved in the interest of the followers of the Ahl al-Bayt (A) from this contact and interaction.
c. He enabled the intellectual leadership on the path of the Ahl al-Bayt (A) to communicate and interact, freely and safely, with all classes of people, on the basis of the principle of nass. Thus the principle of nass became more deeply rooted in the minds of the people and more effective in confronting the evil and misleading designs of the government and the corrupt religious scholars who aided it. It also gained greater acceptance among the upper classes. These positive and negative causes were not all defensive, but were a combination of defensive and offensive. Some of them were defensive and precautionary, while others were aggressive and penetrative.
Thus, after knowing the reasons for al-Ma'mun's offer, these are the possible causes for al-'Imam al-Rida's (A) acceptance of the offer of the heir apparency. What were the results, as far as achievement of the aims was concerned?