قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ : " إِيَّاكُمْ وَالظَّنَّ، إِيَّاكُمْ وَالظَّنَّ، إِيَّاكُمْ وَالظَّنَّ، فَإِنَّ الظَّنَّ أَكْذَبُ الْحَدِيثِ، وَلا تَنَاجَشُوا، وَلا تَحَاسَدُوا، وَلا تَنَافَسُوا، وَلا تَبَاغَضُوا، وَلا تَدَابَرُوا، وَكُونُوا عِبَادَ اللَّهِ إِخْوَانًا "
And the Prophet (peace be upon him) said: "Beware of suspicion, beware of suspicion, for suspicion is often falsehood, and do not artificially raise prices over one another (without the intention to buy), and do not envy one another, and do not outbid one another out of selfishness, and do not create enmity among yourselves, and do not backbite one another, but rather, all of you are servants of Allah, so be brothers to one another."
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