The son of Abu Said al-Khudri reported on the authority of his father that Messenger of Allah ﷺ said: When one of you yawns, he should try to restrain it with cue help of his hand since it is the Satan that enters therein.

حَدَّثَنَا قُتَيْبَةُ بْنُ سَعِيدٍ، حَدَّثَنَا عَبْدُ الْعَزِيزِ، عَنْ سُهَيْلٍ، عَنْ عَبْدِ الرَّحْمَنِ بْنِ أَبِي،
سَعِيدٍ عَنْ أَبِيهِ، أَنَّ رَسُولَ اللَّهِ ﷺ قَالَ
" إِذَا تَثَاوَبَ أَحَدُكُمْ فَلْيُمْسِكْ بِيَدِهِ
فَإِنَّ الشَّيْطَانَ يَدْخُلُ " .