He was succeeded by Aggai, then by Saint Mari, who was ordained about 200 by Serapion of Antioch. Thence came to us in the second century the famous "Peshitta", or Syriac translation of the Old Testament; also Tatian's "Diatessaron", which was compiled about 172 and in common use until Rabbula, Bishop of Edessa (412–435), forbade its use. Among the illustrious disciples of the School of Edessa, Bardaisan (154–222), a schoolfellow of Abgar IX, deserves special mention for his role in creating Christian religious poetry, and whose teaching was continued by his son Harmonius and his disciples.