He transmitted hadith from his father, his grandfather, and Mubarak ibn Fadala. Those who narrated from him include his son al-Maʾmun and others.

He was counted among the noblest of caliphs and the most dignified of kings—a man of pilgrimage, jihad, military expeditions, courage, and sound judgment. His mother was a concubine named Khayzuran.

Fair-skinned, tall, handsome, and good-looking, inclined to stoutness, he possessed eloquence and knowledge, understood well the burdens of the caliphate, and had a keen eye for literature and jurisprudence; grey hair had already streaked his head.

While still a youth, his father sent him to campaign against Byzantine territory during his own reign.

He was born in Rayy in 148 AH.

It is reported that throughout his caliphate he prayed one hundred rakʿahs every day until he died, gave a thousand in charity, loved the scholars, venerated the sacred limits of religion, detested polemical disputation and speculative theology, and would weep over himself, his pastimes, and his sins—especially when admonished.

He enjoyed panegyric, rewarded poets, and even composed poetry himself (1).

On one occasion the preacher Ibn al-Sammak entered his presence; the caliph treated him with exceptional reverence, whereupon he said: “Your humility, despite your noble rank, is nobler than the rank itself….” He then admonished him, and the caliph burst into tears (2).

Al-Fudayl also admonished him once, until he sobbed aloud in his weeping.