There were three basic storylines to this episode of House. Let's break each one down, shall we?
Patient of the Week: It's a shady priest! This guy was seen to start the episode drinking and smoking in his tiny apartment, only to pass out at the site of Jesus and end up in the ER. Cameron assumes he'd just a drunk, but House grabs the file anyway because he needs a "fake case" to annoy Cuddy with (more on that below). After running numerous tests, it's determined the priest has AIDS, which would definitely be problematic.
However, House has an epiphany (unusual, right?) and diagnoses the patient with a far less severe disease. Whne House tells the priest this, the patient considers it an act of God... maybe. See, he has almost as little faith as House at this point, but he sees the string of coincidences that led him here and wonders if there's a greater power at work. House scoffs at this notion, of course, but you can tell he's intrigued a bit by it.
The Fate of Foreteen: House says this couple has to split... or quit. Dating and working together is simply too distracting and makes them bad doctors. The couple tries to call his bluff, but House ends up firing Foreman. This leads to another problem when he can't get a recommendation from Cuddy. As a result, Thirteen tells House that she'll quit and he can re-hire Foreman... but Foreman gets angry at her attempt at assistance.
This leads to a fight, which leads to an apparent break up, which leads to Foreman getting re-hired. To end the episode, though, we see the pair making out on the couch. They actually put on over on House, pretending to break up in order to both keep their jobs. A fine acting job all around!
House and Cuddy: Just sleep with her already, House! Cuddy invites House to a Jewish naming ceremony for her daughter. Throughout the episode, there's a lot of back and forth about whether or not she wants him to actually go and whether or not he will. The usual games between these two. By the end, though, it's clear that Cuddy wants him there. It would mean a lot to her.
It looks like House even recognizes this, but does he show up? Of course not. He plays the piano and drinks alone, while Cuddy can't fully enjoy the event due to House's snub.