The directions and goals contained therein by the participants are accepted with all pleasure. Thus began the preparations for the Church in Central Sulawesi to stand alone. But World War erupted and there was an urgent need to organize the Church in Central Sulawesi. The arrival of the Japanese made the evangelists in Central Sulawesi to form Klasis and appoint Klasis leaders who led the church during the war. After the war was over, the First Synod was held in Tentena on 14-19 October 1947, which took several decisions regarding Church Administration, the Synod Governing Body and the establishment of the Central Sulawesi Christian Church (GKST) which was established on 18 October 1947.

Since its establishment, GKST has started to grow and develop its services. GKST then became a member of the World Council of Churches in 1948 and later became a member of the Communion of Churches in Indonesia (PGI) two years later.

Furthermore, committees were formed to deal with areas of church service such as Theology, Evangelism, Schooling and Education, Unions/Categories, Diakonia, Marriage and Order and Strategy, managing GKST finances and so on. The result of that was the establishment of the GKST Christian Education and College Foundation, the Theology School as a continuation of the Bible Teacher School, the Community Development Foundation, the Christian Fathers' Union/Synode's Commission, the Christian Mothers' Union/Synode Women's Commission, the Christian Youth Fellowship/Synode Youth Commission, and the Youth Commission. The Synod was founded on ; Synod Sunday School Commission.

Since then, GKST has continued to improve itself to provide rescue services to humans as a whole. Therefore, to always review the direction of GKST's blooming movement, Synod sessions are held which are held every few years. Currently GKST consists of 27 classics, which are located in Central Sulawesi (Poso, Morowali, Tojo Una-Una, Parigi Moutong, and Sigi/Donggala/Kodya Palu) and South Sulawesi (North Luwu and East Luwu).