Overview Abdisho bar Brikha claims that Isaac wrote seven volumes. Isaac's known writings comprise a
'First Part', 'Second Part', and 'Third Part'. Passages of a supposed 'Fifth Part' have also been discovered, but there is no academic consensus about whether they are authentic. The 'First Part' alone was translated into Greek in antiquity, and from Greek into various other languages, such as
Slavonic. The 'Second Part' was rediscovered in the 1980s, and the 'Third Part' in the 1990s. Isaac's writings survive in
Syriac manuscripts, and in later translations into languages including Greek, Arabic, Georgian, and Sogdian. Isaac's main influences include
Evagrius Ponticus,
Pseudo-Dionysius,
John the Solitary,
Ephrem the Syrian,
Narsai, and
Theodore of Mopsuestia. In turn, Isaac influenced later Syriac writers such as
John of Dalyatha and
Joseph Hazzaya.
Sebastian Brock has provided a summary as of 2024 of all editions and translations of each of the three known 'Parts' of Isaac's writings. In 1983 the Holy Transfiguration Monastery in
Brookline published an English translation based primarily on the ancient Greek translation of the First Part, though with reference to the original Syriac text. A revised second edition of this translation was published in 2011, with a third printing in 2020. The number and order of homilies in the First Part can vary greatly depending on the manuscript or edition.
Second Part The 'Second Part' contains 41 chapters, of which Chapter 3 is by far the longest. Chapter 3, also known as the 'Headings on Spiritual Knowledge', contains roughly 400 chapters of various lengths, arranged in four centuries. The Second Part was discovered in April 1983 at the
Bodleian Library by
Sebastian Brock, who found that MS syr. e. 7, originally donated by the Assyrian priest
Yaroo Michael Neesan (1853–1937) to the Bodleian Library on 29 June 1898, in fact contained writings of Isaac the Syrian that were hitherto unknown to Western scholars, even though they were regularly read by Syriac readers. After 1983, incomplete manuscripts of Part 2 have been discovered in
Cambridge MS Or. 1144, which is a part of
Bibliothèque Nationale de France, MS syr. 298 (c. 11th-13th century). Chapters 1–3 have been translated into English by Brock (2022) (with Chapters 1–2 previously published in Brock (1997) as well), while an English translation of chapters 4–41, along with the original Syriac text, can be found in Brock (1995). A complete French translation was published by
André Louf (2003), and a partial Greek translation was published by Kavvadas (2006). Selections from Part 2 have been translated into Italian by Bettiolo (1985) and into Catalan by Nin (2005). List of manuscripts containing the 'Second Part': into French by
André Louf (2009), and into Italian by Sabino Chialà (2004, 2011). It is based on Issayi MS 5, held in Tehran, Iran. The manuscript is a 1903 copy of a 14th-century original manuscript that has now been lost. It was discovered by Monsignor Yuhannan Samaan Issayi, the Chaldean archbishop of Tehran, at an antiquarian Jewish bookshop and was kept in his private library. After his death in 1999, Belgian scholar Michel van Esbroek found the manuscript in Issayi's library in Tehran and announced its discovery to the international scholars. Issayi MS 5 has 133 folios, with 111 folios containing 17 homilies that can be attributed to Isaac. There are 14 homilies not found in other texts that are numbered as 1–13 and 16 within Part 3. The other three texts in Issayi MS 5 can also be found in extant Part 1 and Part 2 manuscripts. have been discovered in MS Rahmani 80 (in Sharfet), MS Dawra sir. 694 and MS Dawra sir. 938 (both held in
Baghdad), and Vatican MS sir. 592. Hansbury (2016) contains English translations of two discourses from the Fifth Part. There is currently no consensus among scholars about the authenticity of any of these supposed fragments of the 'Fifth Part'. ==Views on universal reconciliation==