a muslim would not mock their own faith if they actually believed in it? What would they mock? "oh I believe in a God but I think he's silly" Not sure what scenario makes sense here mate. If they did they would be misguided by all accounts.
Bit of a non-sequitur there... How old is your sister, yes or no?
Why are you determined to take things to the extreme?
4 mental blokes are locked in a cell in mental asylum. A local leader comes for a tour of the asylum. The doctors are walking him through the facility when he hears some noise from one of the cells. The leader stops and asks to see what's going on. Behind the bars there are 4 men, 3 of them wildly shouting, the other sat quitely in the corner looking amused.
The leader turns to the doctor and asks him what they're saying. The doctor replies;
"The first man is shouting that he should be released, he claims to be Muhammad and says gods wrath will be upon us for locking him up".
"The second man is shouting that he should be released, he claims to be Jesus and says gods wrath will be upon us for locking him up".
"The first man is shouting that he should be released, he claims to be Moses and says gods wrath will be upon us for locking him up".
"I don't know why the fourth man is sitting there quitely".
At this point the 4th man gets up and calmly walks up to the bars.
"I find these three and their wild claims highly amusing. Each of the claims to be a prophet of God, yet I didn't appoint any of them".
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There you go, a Muslim joke about religion. We do joke about religion, we just don't mock it. Muslims consider Islam to be true, I think Christianity has gotten to the point where most people who ascribe to it in the west, merely consider it a part of their history or culture.