In The Catholicity of Christianity and the Church, Bavinck traces the influence of that dualistic view of the world which is at the heart of pietistic Christianity and finds its roots in the early church:
It is not to be denied that the vision of the world held by the first Christians was, in general, extremely dark. The apologists saw a work of the devil in pagan culture. Not only the theater but also pagan science, philosophy, and art were strongly condemned by many. Wealth, luxury, and earthly goods were regarded with suspicion. Marriage was not condemned, but a celibate life was still prized more highly. A certain tendency toward asceticism arose rather quickly. The hallmark of a true Christian was a contempt for the world and for death. The second and third centuries are filled with dualism and asceticism. 228
From this view, according to Bavinck, comes the mediaeval conception of the kingdom of God, the work of Christ and of the Spirit. This was the view of the church that the Reformers came out from. Bavinck acknowledges that there are differences between the mediaeval view and that of Roman Catholicism in his day. This will be even more the case today, post-Vatican II, but Bavinck’s description of the Roman Catholic view of grace is still broadly valid:
It does not reform and renew that which exists, it only completes and perfects Creation. Christianity is that which transcends and approaches the natural, but it does not penetrate it and sanctify it. With this, Rome, that considers itself to be truly catholic, changes the character of New Testament catholicity…The catholicity of the Christian principle that purifies and sanctifies everything is exchanged for a dualism that separates the supernatural from the natural by considering it as transcendent above the natural. 229
It is not difficult from this to see how it became necessary for Rome to set itself over against culture, the state, society, science, and art. According to Rome, Christianity is exclusively church. Everything depends on this. Outside the church is the sphere of the unholy. The goal had to be to bring about the church's hegemony over everything…. Thus, while the natural order is in itself good, it is of a lower order…worldly art is good but ecclesiastical art is better. Marriage is not rejected, but celibacy is the ultimate Christian ideal. Possessions are legitimate, but poverty is meritorious. Practicing an earthly vocation is not a sin, but the contemplative life of the monk has a greater excellence and worth. 230
This outlook, present in mediaeval Christianity and challenged by the Reformers, re-emerged in similar (but not identical) form in Protestant evangelicalism.