Mishkat al-Masabih
‘Umar reported the Prophet (ﷺ) as saying, "Whenever a man is alone with a woman the devil makes a third.” Tirmidhi transmitted it.
وَعَنْ عُمَرَ عَنِ النَّبِيِّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ قَالَ: «لَا يَخْلُوَنَّ رَجُلٌ بِامْرَأَةٍ إِلَّا كَانَ ثالثهما الشَّيْطَان» . رَوَاهُ التِّرْمِذِيّ
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