Surat Al-'Aĥzāb - سورة الأحزاب

يَا نِسَاءَ النَّبِيِّ لَسْتُنَّ كَأَحَدٍ مِّنَ النِّسَاءِ ۚ إِنِ اتَّقَيْتُنَّ فَلَا تَخْضَعْنَ بِالْقَوْلِ فَيَطْمَعَ الَّذِي فِي قَلْبِهِ مَرَضٌ وَقُلْنَ قَوْلًا مَّعْرُوفًا

Muhsin Khan: O wives of the Prophet! You are not like any other women. If you keep your duty (to Allah), then be not soft in speech, lest he in whose heart is a disease (of hypocrisy, or evil desire for adultery, etc.) should be moved with desire, but speak in an honourable manner.