It is a Syriac Orthodox church located in the city of Mosul, and is considered the oldest church in Mosul. It was previously the residence of the Syrian Orthodox patriarchs in the city. Some unanimous historical sources indicate that St. Thomas Church is one of the oldest currently existing churches in Mosul.
After the Fall of Mosul, the relics of Saint Thomas were taken from the church by Nicodemus Daoud Sharaf, Syriac Orthodox Archbishop of Mosul, and transferred to the Monastery of Saint Matthew on 17 June 2014. The church was destroyed by ISIS after occupying the city of Mosul in 2014. Like other ancient monuments in Mosul, it is part of a planned program to blur historic city landmarks. The church was used as a prison by ISIS insurgents until the city's liberation in 2017.
In July 2019, the first Mass was held in the Church of St. Thomas the Apostle, after the liberation of the city, and the cleaning and temporary rehabilitation of the church by Muslim civil activists, an invitation from them to welcome the return of Christians to the city of Mosul again.