Mar Sabor and Mar Proth, according to Syrian Christians of Kerala, were two Church of the East Bishops believed to have arrived in 825 AD alongside a group of Christian settlers led by a merchant from Persia. Together, they established ecclesiastical institutions in several regions. Revered for their devoutness, they were posthumously recognized as saints by the local ecclesiastical body. The mission is said to have received permission from the then king of Kerala to build a church in Kollam.

The Saint Thomas Christians, also called Syrian Christians of India, Marthoma Suriyani Nasrani, Malankara Nasrani, or Nasrani Mappila, are an ethno-religious community of Indian Christians in the state of Kerala, who, for the most part, employ the Eastern and Western liturgical rites of Syriac Christianity. They trace their origins to the evangelistic activity of Thomas the Apostle in the 1st century. The Saint Thomas Christians had been historically a part of the hierarchy of the Church of the East but are now divided into several different Eastern Catholic, Oriental Orthodox, Protestant, and independent bodies, each with their own liturgies and traditions. They are Malayalis and their mother tongue is Malayalam, which is a Dravidian language. Nasrani or Nazarene is a Syriac term for Christians, who were among the first converts to Christianity in the Near East.