Sahih al-Bukhari 4891

'Urwa related that 'A'isha, the wife of the Prophet, may Allah bless him and grant him peace, informed him that the Messenger of Allah, may Allah bless him and grant him peace, used to examine** those believing women who emigrated to him by this ayat where Allah says, "O Prophet! When believing women come to you pledging allegiance to you ... to ... "Ever-Forgiving, Most Merciful." (60:12) 'Urwa said that 'A'isha said, "When any of the believing women affirmed this condition, the Messenger of Allah, may Allah bless him and grant him peace, would say to her, 'I have taken your allegiance' verbally. By Allah, his hand never touched the hand of a woman during the oath of allegiance. He only received their allegiance by saying, 'I have taken your allegiance on that basis.'" It is corroborated from az-Zuhri from 'Urwa and 'Amra. [* Emigrating from Makka to Madina. This was revealed after the Treaty of al-Hudaybiyya. ** This is to make them swear that they were not leaving out of dislike of a husband, but had only left out of love for Allah and His Messenger and desire for the deen of Allah.]