Sahih Bukhari
Prayers (Salat)
Volume: 001 / Book Number: 008 / Hadith Number: 359
Narrated Mughira bin Shu'ba:
Once I was traveling with the Prophet and he said, "O Mughira! take this container of water." I took it and Allah's Apostle went far away till he disappeared. He answered the call of nature and was wearing a Syrian cloak. He tried to take out his hands from its sleeve but it was very tight so he took out his hands from under it. I poured water and he performed ablution like that for prayers and passed his wet hands over his Khuff (leather socks) and then prayed .