Sahih Bukhari Volume 9, Book 93, Hadith 7216

حَدَّثَنَا مَحْمُودٌ، حَدَّثَنَا عَبْدُ الرَّزَّاقِ، أَخْبَرَنَا مَعْمَرٌ، عَنِ الزُّهْرِيِّ، عَنْ عُرْوَةَ، عَنْ عَائِشَةَ ـ رضى الله عنها ـ قَالَتْ كَانَ النَّبِيُّ صلى الله عليه وسلم يُبَايِعُ النِّسَاءَ بِالْكَلاَمِ بِهَذِهِ الآيَةِ ‏{‏لاَ يُشْرِكْنَ بِاللَّهِ شَيْئًا‏}‏ قَالَتْ وَمَا مَسَّتْ يَدُ رَسُولِ اللَّهِ صلى الله عليه وسلم يَدَ امْرَأَةٍ، إِلاَّ امْرَأَةً يَمْلِكُهَا‏

Narrated By 'Aisha : The Prophet used to take the Pledge of allegiance from the women by words only after reciting this Holy Verse: (60.12) "...that they will not associate anything in worship with Allah." (60.12) And the hand of Allah's Apostle did not touch any woman's hand except the hand of that woman his right hand possessed. (i.e. his captives or his lady slaves).