Musnad Ahmad 1153:921

'Affan narrated to us, he said: Shu'bah narrated to us, from Miqdam ibn Shurayh ibn Hani', he said: I heard my father narrating from 'Aishah, may Allah be pleased with her, that he heard her saying: I was upon a difficult camel, and I began to strike it. The Messenger of Allah, may Allah bless him and grant him peace, said to me: "You must be gentle, for gentleness is not in anything but that it adorns it, and it is not removed from anything but that it disgraces it."