Cafeterian

Cafeterian is a slang term coined by Pile that refers to a theist who claims to be part of a particular religious affiliation (such as a "Christian"), who picks and chooses select aspects of scripture and dogma to follow, while ignoring contradictory or other scriptures, rules and dogma.

Since almost all religious people pick-and-choose how they want to interpret the nature of their faith and its tenets, you could say all theists are "cafeterians" but there's a special brand of theist, usually Christians, who like to spend a lot of time and energy calling themselves "real Christians" and railing against other "fake Christians" who don't follow their particular interpretation of scripture, what Jesus is all about, or other aspects of their faith.

These "cafeterians" basically select what they want to believe in, not unlike one would visit a cafeteria and select specific plates of food, while ignoring everything else.

Here's a classic example of a "cafeterian" diatribe:

If all Jesus said was "love god and love others" then the bible could be a half-page long. Isn't it convenient that this Cafeterian has condensed the entire nature and history of Christianity into this simple sentence. It's up to us to trust him that this guy somehow has figured the whole of Christianity out. Sure.

One might also note the long-standing term "Salad bar theism", the idea being someone who approaches their religion like they do a salad bar, picking only the bits that "taste good" while ignoring the rest.