From what I've heard, the Sincheonji church had a long tradition of sending followers to other churches, hiding their identity, so that they make a lot of friends there, start small clubs and bible studies, and eventually convert them into their own church. (I even heard there were cases when they converted a pastor, winning over a church wholesale, though that might be a bit embellished.)

The problem was so bad that, even before the current epidemic, other "regular" churches had a sign saying "No member of Sincheonji is allowed in our church." So, yeah, not exactly your garden variety Christian church.

When you think about it, this behavior would make Sincheonji a perfect vector for spreading the virus. And that's what happened. Yikes.

I mean, let's not throw stones when we live in glass houses. Pretty much every religion teaches that the others are false teachings.

If there are thousands of people, are they really that secretive?

Now you’re just being intriguing... I have to know now.

All religions spread false teachings.