Youhana of Atharb
Youhana, a stylite ascetic and a priest at the Monastery of Atharb, near Aleppo, was greatly interested in investigation and knowledge. He came to know Jacob of Edessa in the latter's late life and began corresponding with him, investigating historical and ritualistic questions and asking him juristic opinions regarding no less than one hundred legal matters. He received satisfying answers from him. He also corresponded with George, bishop of the Arabs, after Jacob's death. He died in 738.
Youhana, having attained a great knowledge of theological science, wrote an eloquent and significant treatise on the human soul for the Orthodox Syriac clergy according to the views of the church scholars. It is divided into six chapters, covering twenty-two large pages. This treatise was greatly admired by Youhana of Dara, who incorporated it into his Treatise on the Soul. This treatise, which is extant in only one copy, is preserved in the library of Boston in the United States.
He also wrote a short chronograph which was lost except for a few citations by Michael the Great. In addition, he wrote a letter, in eight pages, between 726 and 737, in reply to the priest Daniel of Tay, discussing the theme of the prophecy of Jacob: "The scepter shall not depart from Judah," etc., in which he cited the opinions of some ancient doctors like Severus Sabukht, the great philosopher Jacob of Edessa and George, bishop of the Arabs. John was cited by Bar Salibi in his treatise on Paradise.
Sources:
Patriarch Ignatius Aphram I Barsoum (2003), The Scattered Pearls, A History of Syriac Literature and Sciences, Translated and Edited by Matti Moosa, New Jersey