Sayyiduna Abu Qatadah (may Allah be pleased with him) reports that the Messenger of Allah (peace and blessings be upon him) said: "When any one of you drinks (a beverage or the like), he should not breathe into the vessel, and when he relieves himself, he should not touch his private part with his right hand, and when he cleans himself after relieving himself, he should not clean himself with his right hand."