Patriarch Yaʿqub wrote at least thirty books about the history of the Church, spirituality and liturgy including a History of the Church until the 6th century, a History of the Syrian Church in India, a comparative study of Syriac and Arabic languages, and Personageaphies of  Ephrem the Syrian, Philoxenus of Mabbug, and Yaʿqub of Serugh.
Patriarch Yaʿqub composed a significant corpus of writings on the history of the Church, spirituality, and liturgy, including works on the Church's early period, the Syrian Church in India, linguistic comparisons between Syriac and Arabic, and biographical accounts of influential figures like Ephrem the Syrian, Philoxenus of Mabbug, and Yaʿqub of Serugh.