The Importance of Marriage in the Post-Christian Nation

I actually thought that if marriage is done in churches and in temples and synagogues, then there's a separation of church and state. But the state has adopted principles of religion because it was valuable for society. The question is, should it still be a state thing? And I would argue it should. It used to be for the purity of the bloodline also that we weren't making sure that you were marrying your first cousin or that's it, et cetera. That was a very important role of it.