When one of you yawns, he should keep his mouth shut with the help of his hand, for it is the devil that enters therein.
سَمِعْتُ ابْنًا لأَبِي سَعِيدٍ الْخُدْرِيِّ يُحَدِّثُ أَبِي عَنْ أَبِيهِ قَالَ قَالَ رَسُولُ اللَّهِ ﷺ إِذَا تَثَاوَبَ أَحَدُكُمْ فَلْيُمْسِكْ بِيَدِهِ عَلَى فِيهِ فَإِنَّ الشَّيْطَانَ يَدْخُلُ