Aaron bar Maʿdani received the name of Yuḥanon when he became Metropolitan of Mardin around the year 1230. In 1231/2 he was ordained Maphrian of the East and appointed patr. in December 1252. As patr. he was not recognized by all bishops, some of whom had sworn allegiance to bar Maʿdani’s rival, Dionysios Angur, ordained a few months earlier. Only after the latter’s violent death in 1261 was he accepted as patr. of the whole Church till his death in 1263 in the monastery of Baksimeṭ (Cilicia).

Bar Maʿdani is a typical representative of the Syriac Renaissance. He studied Arabic in Baghdad and, according to Bar ʿEbroyo, he acquired great proficiency in the literary language. He is the author of several Arabic liturgical and moral homilies in rhymed prose. There is some uncertainty whether these are (partly) based on an earlier Syriac original. His collection of Syriac poems deals with different subjects: two poems on the soul, symbolically designated as Poraḥto ‘Bird’, inspired by the imagery and style of Ibn Sīnā’s ‘Recital On the Bird’ and his ‘Ode On the Soul’; on the way of the Perfect; on the invasion of Edessa; on the ascetic Aaron and several other shorter poems on different themes. The authorship of the latter poems deserves closer examination on account of a certain similarity in style with Bar ʿEbroyo’s poetry and the fact that early compilations contain poems of both Bar Maʿdani and Bar ʿEbroyo. Bar Maʿdani also wrote an Anaphora, which was incorporated into later W.-Syr. liturgical compilations.