Riyad as-Salihin

Riyad as-Salihin 884

Saying "Al-Hamdulillah" When Sneezing, Its Reply, and Manners Relating to Sneezing and Yawning
Arabic hadith text
وعن أبي سعيد الخدري رضي الله عنه قال‏:‏ قال رسول الله صلى الله عليه وسلم ‏:‏ ‏"‏إذا تثاءب أحدكم فليمسك بيده علي فيه، فإن الشيطان يدخل‏"‏ ‏(‏‏(‏رواه مسلم‏)‏‏)‏‏.‏
Translation
Abu Sa'id Al-Khudri (May Allah be pleased with him) reported

The Messenger of Allah (ﷺ) said, "When one yawns, he should put his hand over his mouth, otherwise the devil will enter."[Muslim].