casuistry\ KAZH-oo-uh-stree \ , noun;
1. Specious, deceptive, or oversubtle reasoning, esp. in questions of morality.
2. The application of general ethical principles to particular cases of conscience or conduct.
I was unfamiliar with this word, but I have understood the definitions of it for a long time.
I've a friend who won't eat pork because of the dietary laws in Leviticus. I understand his thinking on that and prefer to not knock someone for their religious beliefs and I myself seldom eat pork. (but not for religious reasons) Still, he picks and chooses just what he obeys of all those laws, not being as strict as the laws command, such as using certain utensils/cookware for different tasks, etc. To me, that fits the first definition.
(I'd still rather discuss the Bible with him than his views that the CIA killed JFK, the moon landings were faked and especially how he thinks the Masons are a satanic organization. )
The second definition reminds me of the game of politics; one party's member will be indicted and the other party crows about it. The next week the same thing happens, only it's a vice-versa deal.