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4. Ali ibn Muhammad has narrated from certain persons of our people from Muhammad ibn al-Rayyan who has said the following “Al-Ma’mun did all he could to prove that abu Ja‘far, Muhammad ibn Ali al-Rida عليه السلام was only a young man of worldly desires. However Al-Ma’mun could not succeed. When he became frustrated he gave his daughter in marriage to abu Ja‘far, Muhammad ibn Ali al-Rida عليه السلام . For the ceremony he sent two hundred most beautiful entertaining girls each with a bowl in her hand with a precious pearl in it to well come abu Ja‘far, Muhammad ibn Ali al-Rida عليه السلام when he would sit on the special seat prepared for him. They, however, were not of any attraction to the Imam عليه السلام to disturb him. There was a man called Mukhariq who had a voice, musical skills, a guitar and a tall beard. Al-Ma’mun called him and he said, “O Amir al-Mu’minin, if he is a worldly man I will prove myself as dealing him deadly blows on your behalf.” He sat in front of abu Ja‘far, Muhammad ibn Ali al-Rida عليه السلام and began to bray a hee-haw that made all the people of the house gather around him. He began to play his guitar and sing. He did it for an hour but abu Ja‘far عليه السلام did not pay any attention to the right or left. Then he عليه السلام raised his head and said, “O you, tall bearded one, be pious before Allah.” The narrator has said that the musical instrument and guitar fell off his hand and he could not use his hands thereafter until he died. When Al-Ma’mun asked him about his condition he said, “When abu Ja‘far عليه السلام expressed his disappointment at me it struck me with a huge degree of fear from which I have not been able to relieve myself ever since.”