Musnad Ahmad 1250:13

'Abd al-Samad narrated to us, he said: Ishaq Abu Ya'qub narrated to us, he said: Isma'il ibn 'Abd al-Rahman ibn 'Atiyyah narrated to us, from his grandmother, Umm 'Atiyyah, who said: When the Messenger of Allah (peace and blessings of Allah be upon him) arrived in Medina, he gathered the women of the Ansar in a house. Then he sent 'Umar ibn al-Khattab to them, so he stood at the door and greeted them with peace, and they returned the greeting. He said: "I am the messenger of the Messenger of Allah (peace and blessings of Allah be upon him) to you." They said: "Welcome to the Messenger of Allah (peace and blessings of Allah be upon him) and to his messenger." He said: "You pledge allegiance that you will not associate anything with Allah, nor steal, nor commit adultery, nor kill your children, nor bring forth a slander that you fabricate between your hands and your feet, nor disobey in what is good." They said: "Yes." 'Umar extended his hand from outside the door, and they extended their hands from inside. Then he said: "O Allah, bear witness." He commanded us to go out for the two Eids, the virgins and those who are menstruating. We were forbidden from following funeral processions, and there is no Friday prayer upon us. I asked him about the slander and about His saying: {And they will not disobey you in what is good} [Al-Mumtahanah: 12]. He said: "It is wailing."