Pope Benedict XVI spoke in Germany the other day, and apparently both Catholics and Protestants are disappointed
that he did not work to break down faith barriers and bring the churches closer together. Apparently there are many in Germany asking why old divisions between the faiths still exist. Though not quite the theologian myself, I find the answer quite simply expressed in much of the philosophy of classical liberalism, as a chief reason why we seek to separate the political realm from that of the religious: you cannot compromise on religion. One cannot negotiate or haggle over how to save one's soul. There cannot be a deal struck over how to interpret what is God's law and what is not. Locke handles the issue very well in his Letter Concerning Toleration and Essay Concerning Human Understanding, as to why we must separate the sword and the cross in order to have political peace--politics requires principle, yes, but also compromise, and give-and-take, which cannot exist within religious discourse. There is no room for compromise in true faith. Government must account for this, which then-candidate Obama actually discussed rather well in a speech
a few years ago.
Religions must lay down the sword and be tolerant of each other's existence in human society, but they have no need to break down barriers between each other or negotiate their beliefs with each other. And while religions can have dialogues with each other, can seek where they agree on matters of theology and living, can try find where they can work together towards common goals, they are under no obligation to rectify their beliefs with each other. This "tolerance" does not mean, either, that one faith cannot call another out for its shortcomings or say that only through their own church can one's soul be saved. It just means that it must respect and act within the laws of man. Good for the Pope for not giving into this silly and relativistic idea that one needs to work to break down the barriers between faiths.