Musnad Ahmad 1153:1867

'Abd al-Razzaq narrated to us, he said: Ma'mar informed us, he said: Al-Zuhri said: And 'Urwah informed me, from 'Aishah, that she used to not do that, and she said: "It was only that the Messenger of Allah, peace and blessings of Allah be upon him, descended it, because it was a descent that was more lenient for his departure."