D.G. Hart wonders whether dualism is always such a bad thing after all:

The Westminster Divines in chapters 20 and 31, for starters, talk about the differences between civil and ecclesiastical power, and also say that the church is not to meddle in matters civil. This is dualism in my view. It suggests that the state has authority over the physical sphere of human existence and the church over the spiritual. Yes, there are overlapping areas, such as that the state’s laws imply morality and churches own property. But the basic point is that the church uses a two-edged spiritual sword for her discipline, the state uses a real one....

But while I’m at it, I’ll take a stab at defending religious neutrality, in ways comparable to linguistic neutrality. I do think Kuyperians are good Calvinists when they describe the situation of every person — either he or she is a God-fearer, a covenant-keeper (imperfect) or not. So no one is neutral in this sense. But when I go before a judge, and I am identified as a member of the Orthodox Presbyterian Church, I am pretty confident that a non-Christian can still hear my case impartially without condemning me for the creed I confess. (I’m actually worried more about his politics than his theology or lack thereof.)