On Reasons for Which Al-Ma’mun Martyred Ali ibn Musa Ar-Ridha عليه السلام with Poison

59-3 Tamim ibn Abdullah ibn Tamim al-Qurashi - may God be pleased with him - narrated that his father quoted on the authority of Ahmad ibn Ali Al-Ansari that he asked Aba Salt al-Harawi, “How could Al-Ma’mun - who honored Ar-Ridha’ عليه السلام so much that he designated him عليه السلام to be the successor to his throne - stand to murder Ar-Ridha’ عليه السلام?” Aba Salt al-Harawi replied, “Indeed Al-Ma’mun knew about the degree of nobility of Ar-Ridha’ عليه السلام. That is why he honored him and loved him. The reason that he set Ar-Ridha’ عليه السلام up as the successor to the throne after himself was that he wanted the people to think that Ar-Ridha’ عليه السلام is inclined to worldly affairs, and then Ar-Ridha’ عليه السلام would lose his place in the people’s hearts. However, when what he had plotted did not happen. And the nobility of the Imam عليه السلام was increased amongst the people and his position was strengthened in the hearts of the people. Then Al-Ma’mun invited speakers from the various countries eagerly hoping that they might be able to overcome Ar-Ridha’ عليه السلام in their debate resulting in his deficiencies becoming apparent for the people. However none of them - whether the Jews, the Christians, the Magi, the Sabians, the Brahmans, the unbelievers, the adherers to the doctrine of the eternity of the world, and the opponents from the various Muslim sects were able to defeat Ar-Ridha’’s عليه السلام arguments. And they were all convinced by his arguments and proofs. Then the people said, ‘By God! Ar-Ridha’ عليه السلام is more deserving than Al-Ma’mun to be the Caliph.’ The reporters reported this news to Al-Ma’mun. He got really angry about this and his jealousy increased. However, Ar-Ridha’ عليه السلام did not fear Al-Ma’mun and clearly expressed the truth. Ar-Ridha’ عليه السلام often replied to Al-Ma’mun in such a way that Al-Ma’mun did not like. Then Al-Ma’mun would become angry and hold a grudge against Ar-Ridha’ عليه السلام, but he never made it known. Once all his plots against Ar-Ridha’ عليه السلام failed, he killed him with poison.”