Musnad Ahmad 1153:2384

Asbat ibn Muhammad narrated to us, he said: Mutarrif narrated to us, from Abu Ishaq al-Subay'i, from Abu Ubaydah ibn Abdullah, he said: I said to Aisha: "What is al-Kawthar?" She said: "A river given to the Prophet, may Allah bless him and grant him peace, in the depths of Paradise." He said: I said: "And what are the depths of Paradise?" She said: "Its center; its banks are hollow pearls." These hadiths are the additions of Abdullah. Abdullah said: I found these hadiths from here to the end in my father’s book, in his own handwriting. 26404 - Amir ibn Salih narrated to us, he said: Hisham ibn Urwah narrated to us, from his father, from Aisha, she said: "The Messenger of Allah, may Allah bless him and grant him peace, never struck a woman of his with his hand, nor a servant, nor did he strike anything with his hand at all, except when he was striving in the way of Allah." She said: "Nothing was ever done to the Messenger of Allah, may Allah bless him and grant him peace, for which he would take revenge, unless the sanctities of Allah were violated, in which case he would take revenge for the sake of Allah." She said: "Two matters were never presented to the Messenger of Allah, may Allah bless him and grant him peace, one of which was easier than the other, but that he would take the easier one, unless it was a sin; and if it were a sin, he would be the furthest of people from it."