Nasr al Dawla's vow

Ibn Abi Usaybi'a (13th century), on the vow of the Kurdish Marwanid ruler, Nasr al-Dawlah:

Shaykh Sadīd al-Din ibn Raqiqah, the physician, related to me that the hospital at Mayyāfāriqīn came to be built because a beloved daughter of Nasr al-Dawlah became ill there. Nasr al-Dawlah vowed to donate her weight in silver dirhams to charity if she became well, and when Zāhid al-'Ulamā' treated her and she recovered, he advised Nasr al-Dawlah to dedicate all the silver he was donating to the building of a hospital, which would benefit the people and earn him a great reward and a good reputation. Nasr al-Dawlah ordered the building of the hospital and spent a great amount of money on it. He endowed it with estates that would meet its needs and fitted it out with equipment and all that was needed for it, at great expense. Hence it was unsurpassed in its quality.