Narrated Qatada: Anas bin Malik said, The Prophet used to visit all his wives in a round, during the day and night and they were eleven in number. I asked Anas, Had the Prophet the strength for it? Anas replied, We used to say that the Prophet was given the strength of thirty (men). And Sa`id said on the authority of Qatada that Anas had told him about nine wives only (not eleven).