[Kurn, son of Mogh]

I didn't understand why they voted Leslie instead of Courtney? Maybe they were pissed that she blabbed all the tribe secrets to the other tribe.

They voted her out because she kept making a big deal of how 3 people at the other tribe were Christians. Since she's made it obvious that that's a huge issue for her, she became a future threat. After the merge she'd be like a member of the other tribe and could help pick off her old tribe members (since for her, the Jesus tribe trumps any Survivor Tribe).

Nobody views Courtney as any threat at all. There is always a balance to be struck with the need to win challenges vs the need to eliminate threats.