رِيَاضُ الصَّالِحِينَ
Riyad as-Salihin 884
The Book of Greetings
Saying "Al-Hamdulillah" When Sneezing, Its Reply, and Manners Relating to Sneezing and Yawning
وَعَنْ أَبِي سَعِيدٍ الْخُدْرِيِّ رَضِيَ اللَّهُ عَنْهُ قَالَ: قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ : إِذَا تَثَاءَبَ أَحَدُكُمْ فَلْيُمْسِكْ بِيَدِهِ علي فِيهِ، فَإِنَّ الشَّيْطَانَ يَدْخُلُ ((رَوَاهُ مُسْلِم)).
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].
Riyad as-Salihin, 884