Narrated Abu Qatada: The Prophet said, "Whenever anyone of you makes water he should not hold his penis or clean his private parts with his right hand. (And while drinking) one should not breathe in the drinking utensil ."
Hadith Referenceصحيح البخاري / كتاب الوضوء / 154
Hadith Gradingمحدثین:أحاديث صحيح البخاريّ كلّها صحيحة