Sahih Muslim Book 26, Hadith Number 5441.

Chapter : Curing of the patient with the recitation of Mu’awwidhatan (Suras CXIII., CXIV).

This hadith has been narrated through some other chains of transmitters but with a slight variation of wording. In the hadith transmitted on the authority of Yanus and Ziyari (the words are): “When Allah’s Apostle (may peace be upon him) fell ill, he blew over his body by reciting Mu’awwidhatan and rubbed him with his hand.