The year 166 AH began. In Muḥarram al-Rashīd returned from the lands of the Byzantines and entered Baghdad in magnificent pomp, the Byzantines themselves accompanying him and carrying the jizya in gold and other valuables.

That same year al-Mahdī took the oath of allegiance for his son Hārūn, to succeed Mūsā al-Hādī, and granted him the honorific al-Rashīd.

Also in this year al-Mahdī became angry with Yaʿqūb ibn Dāwūd. The latter had long enjoyed his favour: the Caliph had made him vizier and raised his standing to the point that the whole administration of the caliphate had been placed in his hands. Concerning this, Bashshār ibn Burd said:

Banu Umayyah, awake—your slumber has lasted far too long, (1)
… for the caliph is Yaʿqūb ibn Dāwūd.
Your caliphate has been lost, my people; so seek (2)
the vicegerent of God amid the wine-skin and the lute.

Slanderers and tale-bearers never ceased to shuttle between him and the Caliph until they turned the latter against him; yet whenever they denounced him, he would enter, set matters right, and regain favour—until the incident I am about to relate.

One day he entered upon al-Mahdī in a splendid audience hall spread with every kind of carpet and coloured silk; round that place were trees (3) heavy with many sorts of blossom.

The Caliph asked, “Yaʿqūb, how do you find this assembly of ours?”
He replied, “Commander of the Faithful, I have never seen anything finer.”
The Caliph said, “It is yours, with everything in it—and this slave-girl as well, that your joy may be complete. Yet I have a request I would like you to fulfil.”

I said, “And what is it, Commander of the Faithful?”
He answered, “Not until you first say ‘Yes.’ ”
I said, “Yes; I hear and obey.”

“By Allah?” he pressed.
“By Allah,” I replied.
“And by the life of my head?”
“By the life of your head.”
“Place your hand upon my head and swear it,” he said, and I did so.

He then said, “There is an Alid here whom I wish you to relieve me of”—it appears he was al-Ḥasan ibn Ibrāhīm ibn ʿAbd Allah ibn al-Ḥasan ibn al-Ḥasan ibn ʿAlī ibn Abī Ṭālib.
I said, “Very well.”

“And be quick about it,” he added. Then he ordered everything in that hall to be moved to my house, granted me one hundred thousand dirhams, and gave me that slave-girl; nothing had ever delighted me so much as she did.

When she reached my residence I secluded her in the women’s quarters. I then sent for that Alid; he was brought, sat with me, and spoke, and I had never seen anyone more intelligent or perceptive.

He said to me, “Yaʿqūb, will you meet Allah bearing my blood, when I am a descendant of Fāṭimah, daughter of the Messenger of Allah ﷺ?”

I replied, “By Allah, no. Go wherever you wish.”
He said, “I choose such-and-such a land.”
I said, “Go as you please, only see that al-Mahdī does not discover you, lest you perish—and I with you.”

He departed, and I arranged for two men to escort him