In the Quran much is written about what is wrong and what is right.
If a Muslim knows that something is wrong, and still does it (or that something is right and doesn't do it) - is he still considered a Muslim, or how strict does it get? What does the Quran say about it? What are the consequences?
Please try to get as much cites in your answer as possible! Thank you indeed!
I ask this question as for example in 5:51 it is written that one who takes Christians and Jews as allies (or friends) is one of them - and therefore not a Muslim anymore. And I wondered... wow this is pretty strict. But I don't want to hear "no it's not that strict, don't take it that seriously" but the truth! How strict does it get and what does the Quran say about "just living the life" and just claiming to be a Muslim but not really caring what the Quran really says... or disobeying some things the Quran tells.