Narrator:Abu Hurayrah
حَدَّثَنَا عَلِيُّ بْنُ حُجْرٍ، أَخْبَرَنَا إِسْمَاعِيلُ بْنُ جَعْفَرٍ، عَنِ الْعَلاَءِ بْنِ عَبْدِ الرَّحْمَنِ، عَنْ أَبِيهِ، عَنْ أَبِي هُرَيْرَةَ، أَنَّ النَّبِيَّ صلى الله عليه وسلم قَالَ
" التَّثَاؤُبُ فِي الصَّلاَةِ مِنَ الشَّيْطَانِ فَإِذَا تَثَاءَبَ أَحَدُكُمْ فَلْيَكْظِمْ مَا اسْتَطَاعَ "
Abu Hurayrah (may Allah be pleased with him) reported that the Prophet (may Allah's peace and blessings be upon him) said: "Yawning inside the prayer is from the devil, so if anyone of you yawns, let him suppress it as much as he can."
Reported by At-Tirmidhi (No. 370), Al-Bukhari (No. 3289), Muslim (No. 2994) and Ahmad (No. 8797).