Sayyidah Aishah (may Allah be pleased with her) said that the Prophet (peace and blessings be upon him) used to take the pledge from women on the things that Allah Almighty has stated in this verse: "O Prophet, when the believing women come to you pledging to you that they will not associate anything with Allah, nor steal, nor commit adultery, nor kill their children, nor bring forth a slander they have invented between their hands and their feet, nor disobey you in what is right, then accept their pledge and ask Allah's forgiveness for them. Indeed, Allah is Forgiving, Merciful." [Surah al-Mumtahanah: 12] And Sayyidah Aishah (may Allah be pleased with her) said that he (peace and blessings be upon him) never touched the hand of any woman (who was not his own).
This is the wording of the narration of Ali (bin Abdullah al-Madini); in the narration of Ahmad (it says that) the Messenger of Allah (peace and blessings be upon him) used to take the pledge from women by speech, with this verse.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب قتال أهل البغي / 16566
Sayyidah Aishah (may Allah be pleased with her) said that when the women came to him (peace and blessings be upon him) having emigrated, he (peace and blessings be upon him) would take their pledge of allegiance on verse 12 of Surah al-Mumtahanah: "O Prophet, when the believing women come to you pledging allegiance to you" [Surah al-Mumtahanah: 12]. When they affirmed it, he would say: "You have indeed given your pledge." And the Prophet (peace and blessings be upon him) never touched the hand of any unrelated woman.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب قتال أهل البغي / 16567
Sayyidah Umaymah bint Ruqayqah (may Allah be pleased with her) said: I and many other women came to the Prophet (peace and blessings be upon him) to pledge allegiance, and we said: O Messenger of Allah (peace and blessings be upon him)! We pledge allegiance to you that we will not associate partners (with Allah), nor steal, nor commit adultery, nor kill our children, nor bring forth any slander, and that we will not disobey you in what is right. He (peace and blessings be upon him) said: "As far as you are able." She said: We said: Allah and His Messenger are more merciful to us than we are to ourselves, so come, let us pledge allegiance at your hand. He (peace and blessings be upon him) said: "I do not shake hands with women; my word to a hundred women is just like my word to one woman."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب قتال أهل البغي / 16568