عن عائشة رضي الله عنها أن رسول الله صلى الله عليه وسلم كان إذا اشتكى نفث على نفسه بالمعوذات ومسح عنه بيده فلما اشتكى وجعه الذي توفي فيه طفقت أنفث على نفسه بالمعوذات التي كان ينفث وأمسح بيد النبي صلى الله عليه وسلم عنه وفي رواية أخرى لها قالت وأمسح بيد نفسه لبركتها ( صحيح بخاري #4439،5735 )

It is reported from Hazrat ‘Aa’ishah (radhiyallahu ‘anha) that whenever Rasulullah (sallallahu ‘alaihi wasallam) would fall ill, he would recite the Mu‘awwizaat (words of seeking protection i.e. Surah Falaq and Surah Naas and in some narrations, Surah Ikhlaas) and blow upon himself (i.e. he would blow into his hands) and pass his hands over his blessed body. When he (sallallahu ‘alaihi wasallam) fell into his final illnesss (and was unable to recite and pass his blessed hands over his body), I began to recite the Mu‘awwizaat which he would recite and blow on his body, and I would blow into the blessed hand of Rasulullah (sallallahu ‘alaihi wasallam) and pass it over his body.” In another narration, Hazrat ‘Aa’ishah (radhiyallahu ‘anha) mentioned, “I would blow into the blessed hand of Rasulullah (sallallahu ‘alaihi wasallam) and thereafter pass it over his body on account of his hand having the blessing (i.e. I would not blow into my own hands as my hands do not possess the blessing that is in the hand of Rasulullah (sallallahu ‘alaihi wasallam)).”