Kadeesa Orthodox Church is one of the oldest parish of the Malankara Orthodox Syrian Church and is the Mother Parish of the Mavelikara Diocese. The word Kadeesa refers to ‘All Saints’ and the church is one of the three churches dedicated to All Saints. Ancient church history evidences that it was built by two Assyrian Monks – Mar Sabor and Mar Aphroth in 825 AD on the land generously donated by the then Maharaja. Since its consecration the church and its members took active role in all the management of the Malankara Orthodox Syrian Church – India. The Kadeesa Orthodox church has several credentials to its credit. It was one of the forty four churches that participated in the famous Koonan Kurusu Sathaym in 1653. Further three members of the church represented the Mulanthuruthy Synod in 1876. The Most Rev. Kayamkulam Philipose Remban, who had translated Aramen Bible into Malayalam was a member of the parish.

Mar Sabor and Mar Aphroth, revered as the founding figures of Kadeesa Orthodox Church in Kayamkulam, are celebrated for their monumental contributions to the Christian heritage of Kerala. Arriving in 823 AD, these Assyrian bishops, with the support of a Nestorian merchant, received royal sanction to establish a church in Kollam, laying the foundation for Christianity's growth in the region. Their legacy extends to the Kadeesa Church, integral in shaping the Malankara Orthodox Syrian Church's history and participating in significant ecclesiastical events, like the Koonan Kurisu Sathaym and the Mulanthuruthy Synod, reflecting their enduring influence in Kayamkulam's religious and communal life.