The Prophet ﷺ said, "Allah loves sneezing but dislikes yawning; so if anyone of you sneezes and then praises Allah, every Muslim who hears him (praising Allah) has to say Tashmit to him. But as regards yawning, it is from Satan, so if one of you yawns, he should try his best to stop it, for when anyone of you yawns, Satan laughs at him." (Using translation from Bukhārī 6226)
أَنَّ رَسُولَ اللهِ ﷺ قَالَ إنَّ اللهَ يُحِبُّ الْعُطَاسَ وَيَكْرَهُ التَّثَاؤُبَ فَإِذَا عَطَسَ أَحَدُكُمْ فَلْيَقُلِ الْحَمْدُ لِلَّهِ وَحَقٌّ عَلَى مَنْ سَمِعَهُ أَنْ يَقُولَ يَرْحَمُكَ اللهُ وَأَمَّا التَّثَاؤُبُ فَإِنَّمَا هُوَ مِنَ الشَّيْطَانِ فَإِذَا تَثَاءَبَ أَحَدُكُمْ فَلْيَرُدَّهُ مَا اسْتَطَاعَ فَإِنَّ أَحَدَكُمْ إِذَا تَثَاءَبَ فَقَالَ هَاهْ هَاهْ ضَحِكَ مِنْهُ الشَّيْطَانُ