Abu Salih says that once I was present in the service of Hazrat Umm Salamah. During that time, one of her nephews also arrived and he performed two rak‘ahs in her house. During the prayer, when he was about to go into prostration, he blew to remove the dust, so Hazrat Umm Salamah said to him, "Nephew, do not blow, because I heard the Prophet (peace be upon him) once say to his servant whose name was Yasar, and he too had blown, 'Let your face become dusty for the sake of Allah.'"