Religion. You automatically have something in common, and religious people are usually of a high quality because they live for something more than just themselves, as opposed to secular people. Of course, there are terrible, and I mean truly terrible, people in religious communities, and you should identify them and then stay the hell away from them. But the good ones are REALLY good. As an added bonus, you get to gr…
I'd say it's the opposite, but that's just me.