In 1947 the liberal Protestant minister Willem Banning drafted a new programme for the Labour Party, in which the party dropped the Marxist view of history and class struggle. New Labour in the Netherlands was envisioned as a party that strove for a democratic and just society. Banning's role in reforming the Labour Party was part of his broader project of breaking down structures of socio-political segregation that had existed since the end of the nineteenth century. Banning argued that the Labour Party had to abandon its atheist ideology to open up to Protestants and Catholics. This article will examine Banning's views and ideals and show how he contributed to the transformation of Labour into a social democratic party and seek answer to the question: how could a liberal Protestant minister become the main ideologue of the Labour Party?