Regency Between the Imam and al-Mamoon

While researching the motives which prompted al-Mamoon to force Imam al-Rida (A.S.) to be his heir to the throne, we will find out that they were far-sighted political motives al-Mamoon hoped thereby to achieve selfish gains for both himself and the Abbaside caliphate, for al-Mamoon was quite an intelligent man in selecting Imam al-Rida (A.S.) for this post since he represented the opposition group. But Imam al-Rida (A.S.), upon rejecting his selection for this post, proved to be more aware of al-Mamoon and his aims than al-Mamoon had thought. Al-Harawi quotes the Imam saying: "By God! Al-Rida did not accept this matter willingly, and he was transported to Kufa against his wish, then he was taken from there, passing by Basrah and Persia, to Marw."90

Notes:

90 Uyoon al-Akhbar, chapter on al-Rida, Vol. 2, p. 141

Adapted from: "Imam al-Ridha (a.s.), A Historical and Biographical Research" by: "Muhammad Jawad Fadlallah"