Elijah of Nisibis

[10] On Sunday, 15 February 1002, he was consecrated bishop of Beth Nuhadra (present-day Dohuk, Iraq) by Yohannan, who had become the Patriarch of the Church of the East in 1000[9] by appealing directly to the Abbasid governor at Shiraz without regard to the usual election procedures.

[9][12] From 15–29 July 1026, he paid a series of visits—the "Seven Sessions"—to the Abbasid vizier Abu'l-Qasim al-Husayn ibn Ali al-Maghribi to discuss Christian doctrines and other topics.

Elijah is best known for his Chronography or Chronology (Arabic: Kitāb al-Azmina; Latin: Opus Chronologicum), which forms an important source concerning the history of Sassanid Persia.

[16] His treatment of calendrical systems has tables for computation of the Syriac and Persian new years and includes several Zoroastrian calendars, along with their feasts and holidays.

Elijah's Book of Sessions or Dialogues[19] (Arabic: Kitāb al-Majālis) claims to relate his conversations during his seven visits to the Abbasid vizier Abu'l-Qasim al-Husayn ibn Ali al-Maghribi.

[21] In order, the chapters cover:[22] According to Elijah's account, the vizier asking for the meetings after he had experienced a miraculous cure at the hands of a Christian monk, causing him to reconsider his previous understanding of their faith as polytheistic and unfaithful to God.

His guide to "rational management" of anxiety (Arabic: Kitāb dafʾ al-Hamm) is also dedicated to the Abbasid vizier, whom he claims requested such a book during their sessions together.

[25] His "Letter on the Unity of the Creator and Trinity of His Hypotases" (Arabic: Risāla Fī Wahdāniyyat al-Khāliq wa-Tathlīth Aqānīmihi) states the arguments for trinitarianism for a curious Islamic judge.

[4] His "Letter on the Merit of Chastity" (Arabic: Risāla fī Fadīlat al-ʿAfāf) attempts to refute Muʿtazilī al-Jāhiz's (d. 869) arguments in favor of physical pleasure.