Several Syriac chronicles preserve detailed accounts of the Sabbatical Year Earthquakes of 749 CE, offering rich narratives of their effects. Among these, both Michael the Syrian and Chronicon Ad Annum 1234 provide extensive descriptions of seismic effects, primarily associated with the Talking Mule Quake. Their information likely derived from the mostly lost chronicle of Dionysius of Tell Mahre, whose own source in turn may have been the entirely lost chronicle of Theophilus of Edessa.

In his preface, Dionysius of Tell Mahre explicitly states that he used Theophilus of Edessa as a source (Hoyland, 1997: 416–419). Theophilus, then in his fifties and residing in the region, was a contemporary witness to the Sabbatical Year Earthquakes. He later served as court astrologer to Al-Mahdi, the third Abbasid Caliph. At the time of the earthquakes, Al-Mahdi was only four or five years old and living near the southern Arava at Humeima. Theophilus would therefore have possessed direct, first-hand knowledge of these events.

Through the transmission of his work via Dionysius of Tell-Mahre, Theophilus appears to have provided a substantial foundation of seismic information — subsequently filtered through later compilations into the accounts of Michael the Syrian, the Chronicon Ad Annum 1234, and possibly other sources. Although the Chronicle of Theophilus is now lost, Hoyland (2011) has attempted to reconstruct it from dependent materials, and that reconstruction is presented in this catalog.