Abu Qatadah narrated from his father that the Prophet said: ‘When one of you urinates, let him not hold his private part with his right hand. When he defecates, let him not wipe with his right hand (as it is also forbidden to use materials like bones for cleaning). When he drinks, let him not breathe into the vessel’ (see also the related etiquette regarding the direction one should face).’
Sahih Bukhari – Book of Ablution
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