Why was Muhhamad so dumb?
Because he had dumber followers & could afford being dumb!
In Quran 033.053, Allah tells guests to be circumspect in barging into Muhammad's house, only come when invited & leave immediately after eating, without lingering for gossip, because such stuff
annoy Muhammad, but while Mo is shy about asking guests to leave, Allah isn't shy in telling them these stuff!
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Any smart follower would realise that its
extremely suspicious, to say the least,that the Creator of the Universe cares about the length of time guests spend in Mo's house, & is asking guests to leave as Muhammad is
shy to tell them so himself, but Muhammad's followers still believed him!
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Quran 033.053
YUSUFALI: O ye who believe! Enter not the Prophet's houses,- until leave is given you,- for a meal, (and then) not (so early as) to wait for its preparation: but when ye are invited, enter; and when ye have taken your meal, disperse, without seeking familiar talk. Such (behaviour) annoys the Prophet: he is ashamed to dismiss you, but Allah is not ashamed (to tell you) the truth. And when ye ask (his ladies) for anything ye want, ask them from before a screen: that makes for greater purity for your hearts and for theirs. Nor is it right for you that ye should annoy Allah's Messenger, or that ye should marry his widows after him at any time. Truly such a thing is in Allah's sight an enormity.
PICKTHAL: O Ye who believe! Enter not the dwellings of the Prophet for a meal without waiting for the proper time, unless permission be granted you. But if ye are invited, enter, and, when your meal is ended, then disperse. Linger not for conversation. Lo! that would cause annoyance to the Prophet, and he would be shy of (asking) you (to go); but Allah is not shy of the truth. And when ye ask of them (the wives of the Prophet) anything, ask it of them from behind a curtain. That is purer for your hearts and for their hearts. And it is not for you to cause annoyance to the messenger of Allah, nor that ye should ever marry his wives after him. Lo! that in Allah's sight would be an enormity.
SHAKIR: O you who believe! do not enter the houses of the Prophet unless permission is given to you for a meal, not waiting for its cooking being finished-- but when you are invited, enter, and when you have taken the food, then disperse-- not seeking to listen to talk; surely this gives the Prophet trouble, but he forbears from you, and Allah does not forbear from the truth And when you ask of them any goods, ask of them from behind a curtain; this is purer for your hearts and (for) their hearts; and it does not behove you that you should give trouble to the Messenger of Allah, nor that you should marry his wives after him ever; surely this is grievous in the sight of Allah.