Musnad Ahmad 1153:703

Abu Sa’id narrated to us, he said: Abu ‘Awanah narrated to us, he said: ‘Umar narrated to us, from his father, from ‘Aisha, she said: I was accused of what I was accused of while I was heedless, and some of that reached me thereafter. While the Messenger of Allah (peace and blessings of Allah be upon him) was with me, revelation came to him, and whenever revelation came to him, a state similar to slumber would seize him. While he was sitting with me, the revelation was sent down upon him. He raised his head while wiping his forehead, and said: "Rejoice, O ‘Aisha." I said: "By the praise of Allah, the Mighty and Majestic, not by your praise." Then he recited: "{Those who accuse chaste women...}" [An-Nur: 23] until he reached: "{...are innocent of what they say.}" [An-Nur: 26]