None of you should hold his penis with his right hand while urinating, nor wipe himself after answering the call of nature using his right hand, nor breathe into the vessel

The Prophet (may Allah's peace and blessings be upon him) clarified here some manners as he forbade men from holding their penis with their right hand while urinating and forbade the act of removing impurity from the private parts, front or back, with the right hand because the right hand is meant to be used for noble matters. He also forbade breathing into the vessel from which one is drinking.