Sahih Bukhari Volume 8, Book 76, Hadith Number 517.

Narated By ‘Aisha : There was a leather or wood container full of water in front of Allah’s Apostle (at the time of his death). He would put his hand into the water and rub his face with it, saying, “None has the right to be worshipped but Allah! No doubt, death has its stupors.” Then he raised his hand and started saying, “(O Allah!) with the highest companions.” (See Qur’an 4:69) (and kept on saying it) till he expired and his hand dropped.”