This article uses the early thought and career of the Indian Mar Thoma Christian and Marxian theologian M. M. Thomas to investigate the connections between ecumenism’s theology of communism and its engagements with anti-colonial politics and decolonization in the 1940s and 1950s. The article situates Thomas’ efforts to reconcile Marxian doctrine with Christian faith within the movement’s institutional practices for combating the entropic effects of modern secular civilization and Cold War polarization. Tracing Thomas’ ascent from Christian Marxist youth circles in south India to leadership positions in the World Student Christian Federation and the World Council of Churches, the article highlights the central role of his theology in establishing ‘revolutionary’ postcolonial social transformation as the object of Christian global governance in the post-war era.