St. Isaac was born in the region of Qatar on the western shore of the Persian Gulf. When still quite young, he entered a monastery with his brother. His fame grew as a holy man and teacher. He was subsequently ordained bishop of Nineveh, the former capital of Assyria to the north, but requested to abdicate after only five months. He then went south to the wilderness of Mount Matout, a refuge for anchorites. There he lived in solitude for many years studying the Scripture, but eventually blindness and old age forced him to retire to the monastery of Rabban Shabur, where he reposed and was buried. His feast day is January 28.
St. Isaac is fully accepted as a saint in the Orthodox Church, though during his lifetime, he was canonically a member of the Church of the East, a church that has been associated with the Nestorian heresy, although that charge is contested today. His writings nevertheless came to be extremely popular in Orthodox monastic circles and are well-known for their Orthodoxy. Most contemporary Nestorians rejected St. Isaac's three theses, which, although they are not known in their exact form, were Orthodox and incompatible with the Nestorian heresy. One of his extant prayers to Christ makes it difficult for one to maintain that the holy monk was a Nestorian. Veneration for him grew, and he came to be incorporated into the Orthodox calendar of saints.
"Be persecuted, rather than be a persecutor. Be crucified, rather than be a crucifier. Be treated unjustly, rather than treat anyone unjustly. Be oppressed, rather than zealous. Lay hold of goodness, rather than justice."
"A small but always persistent discipline is a great force; for a soft drop falling persistently, hollows out hard rock."
"The Lord's Day is a mystery of the knowledge of the truth that is not received by flesh and blood, and it transcends speculations. In this age there is no eighth day, nor is there a true Sabbath. For he who said that `God rested on the seventh day,' signified the rest [of our nature] from the course of this life, since the grave is also of a bodily nature and belongs to this world. Six days are accomplished in the husbandry of life by means of keeping the commandments; the seventh is spent entirely in the grave; and the eighth is the departure from it." -- The Ascetical Homilies, I
"Why do you trouble yourself in a house that is not your own? Let the sight of a dead man be a teacher for you concerning your departure from hence."
"The knowledge of the Cross is concealed in the sufferings of the Cross."
"The man who follows Christ in solitary mourning is greater than he who praises Christ amid the congregation of men."
"Why do you increase your bonds? Take hold of your life before your light grows dark and you seek help and do not find it. This life has been given to you for repentance; do not waste it in vain pursuits."
- Ascetical Homilies of Saint Isaac the Syrian (1985). ISBN 978-0913026557.
- The Ascetical Homilies of Mar Isaac of Nineveh (2007). ISBN 978-1593333898. (Texts of the homilies are in Syriac.)
- Hilarion Alfeyev, The Spiritual World of Isaac the Syrian (2004). ISBN 978-0879077754.
- isaacthesyrian.com: A collection of resources on St. Isaac
- Pearls from Saint Isaac of Syria
- PEARLS of Saint Isaac from Syria compiled by Fr. Pius Sammut
- OCA - Lives of all saints commemorated on January 28 (including St. Isaac the Syrian the Bishop of Nineveh)
- St. Isaac of Nineveh