It is narrated from Sayyiduna Abu Hurairah (may Allah be pleased with him) that the Prophet (peace and blessings of Allah be upon him) said: "When one of you yawns, he should try to restrain it as much as possible."
Hadith Referenceالادب المفرد / كتاب العطاس والتثاؤب / 942
Hadith Gradingالألبانی:صحيح
Hadith Takhrij«صحيح : صحيح مسلم ، الزهد و الرقائق ، ح : 2994 و أحمد : 397/2»
Explanation & Benefits
Shaykh Maulana Usman Muneeb
Benefits and Issues: It has already been clarified in the previous pages that yawning is from Shaytan and is a sign of laziness, which should be prevented as much as possible. The method for this is to place the hand in front of the mouth and try to suppress it, and no sound should be made.
Source: Fadlullah al-Ahad: Urdu Commentary on al-Adab al-Mufrad, Page: 942