Ablutions (Wudu')
Bukhari :: Book 1 :: Volume 4 :: Hadith 201
Narrated 'Abdullah bin 'Umar:
Sa'd bin Abi Waqqas said, "The Prophet passed wet hands over his Khuffs." 'Abdullah bin 'Umar asked Umar about it. 'Umar replied in the affirmative and added, "Whenever Sa'd narrates a Hadith from the Prophet, there is no need to ask anyone else about it."