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كتاب الطلاق
68  
Divorce
(20)
Chapter: If an idolatress or a Christian woman becomes a Muslim while she is the wife of Dhimmi or a Mushrik at war with the Muslims?
(20)
باب إِذَا أَسْلَمَتِ الْمُشْرِكَةُ أَوِ النَّصْرَانِيَّةُ تَحْتَ الذِّمِّيِّ أَوِ الْحَرْبِيِّ‏.‏
Sahih al-Bukhari 5288

Narrated `Aisha:

(the wife of the Prophet) When believing women came to the Prophet (ﷺ) as emigrants, he used to test them in accordance with the order of Allah. 'O you who believe! When believing women come to you as emigrants, examine them . . .' (60.10) So if anyone of those believing women accepted the above mentioned conditions, she accepted the conditions of faith. When they agreed on those conditions and confessed that with their tongues, Allah's Messenger (ﷺ) would say to them, "Go, I have accepted your oath of allegiance (for Islam). By Allah, and hand of Allah's Messenger (ﷺ) never touched the hand of any woman, but he only used to take their pledge of allegiance orally. By Allah, Allah's Messenger (ﷺ) did not take the pledge of allegiance of the women except in accordance with what Allah had ordered him. When he accepted their pledge of allegiance he would say to them, "I have accepted your oath of allegiance."

حَدَّثَنَا ابْنُ بُكَيْرٍ، حَدَّثَنَا اللَّيْثُ، عَنْ عُقَيْلٍ، عَنِ ابْنِ شِهَابٍ،‏.‏ وَقَالَ إِبْرَاهِيمُ بْنُ الْمُنْذِرِ حَدَّثَنِي ابْنُ وَهْبٍ، حَدَّثَنِي يُونُسُ، قَالَ ابْنُ شِهَابٍ أَخْبَرَنِي عُرْوَةُ بْنُ الزُّبَيْرِ، أَنَّ عَائِشَةَ ـ رضى الله عنها ـ زَوْجَ النَّبِيِّ صلى الله عليه وسلم قَالَتْ كَانَتِ الْمُؤْمِنَاتُ إِذَا هَاجَرْنَ إِلَى النَّبِيِّ صلى الله عليه وسلم يَمْتَحِنُهُنَّ بِقَوْلِ اللَّهِ تَعَالَى ‏{‏يَا أَيُّهَا الَّذِينَ آمَنُوا إِذَا جَاءَكُمُ الْمُؤْمِنَاتُ مُهَاجِرَاتٍ فَامْتَحِنُوهُنَّ‏}‏ إِلَى آخِرِ الآيَةِ قَالَتْ عَائِشَةُ فَمَنْ أَقَرَّ بِهَذَا الشَّرْطِ مِنَ الْمُؤْمِنَاتِ فَقَدْ أَقَرَّ بِالْمِحْنَةِ، فَكَانَ رَسُولُ اللَّهِ صلى الله عليه وسلم إِذَا أَقْرَرْنَ بِذَلِكَ مِنْ قَوْلِهِنَّ قَالَ لَهُنَّ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏"‏ انْطَلِقْنَ فَقَدْ بَايَعْتُكُنَّ ‏"‏، لاَ وَاللَّهِ مَا مَسَّتْ يَدُ رَسُولِ اللَّهِ صلى الله عليه وسلم يَدَ امْرَأَةٍ قَطُّ، غَيْرَ أَنَّهُ بَايَعَهُنَّ بِالْكَلاَمِ، وَاللَّهِ مَا أَخَذَ رَسُولُ اللَّهِ صلى الله عليه وسلم عَلَى النِّسَاءِ إِلاَّ بِمَا أَمَرَهُ اللَّهُ يَقُولُ لَهُنَّ إِذَا أَخَذَ عَلَيْهِنَّ ‏"‏ قَدْ بَايَعْتُكُنَّ ‏"‏‏.‏ كَلاَمًا‏.‏
Reference : Sahih al-Bukhari 5288
In-book reference : Book 68, Hadith 37
USC-MSA web (English) reference : Vol. 7, Book 63, Hadith 211
  (deprecated numbering scheme)