Caution: Translations of Quran and Ḥadīth may lead to possible misapplications and misinterpretations. This site is intended for students of sacred knowledge that are proficient in comprehending classical Arabic and have a strong foundation in Islamic sciences. Also note that religious injunctions rely on several aspects beyond what one may glean through reading individual aḥādīth.
bayhaqi:3361my father

[Machine] We used to pray with the Messenger of Allah ﷺ in a battle. He smiled during his prayer, and when he finished his prayer, we said, "O Messenger of Allah, we saw you smiling." He said, "Mikael passed by me with traces of dust on his wings, as he was returning from seeking the people's needs, and he smiled at me, so I smiled at him." Al-Wazi' ibn Nafi' al-Qa'ili al-Jazari spoke about it, and Al-Waqidi narrated it in the battles. It has also been narrated in the book of purification from Abu Sufyan from Jabir that whoever laughs in prayer should repeat the prayer but not repeat the ablution. And we have also narrated from Abu Musa al-Ash'ari that he said in a story narrated from him: whoever among you laughs, let him repeat the prayer and mention the same from Ibn Mas'ud.  

البيهقي:٣٣٦١أَخْبَرَنَاهُ أَبُو سَعْدٍ أَحْمَدُ بْنُ مُحَمَّدٍ الصُّوفِيُّ أنبأ أَبُو أَحْمَدَ بْنُ عَبْدِ اللهِ بْنِ عَدِيٍّ الْحَافِظُ أنبأ أَبُو يَعْلَى أنبأ عَمْرٌو النَّاقِدُ ثنا عَلِيُّ بْنُ ثَابِتٍ الْجَزَرِيُّ ثنا الْوَازِعُ بْنُ نَافِعٍ عَنْ أَبِي سَلَمَةَ عَنْ جَابِرِ بْنِ عَبْدِ اللهِ ؓ قَالَ

كُنَّا نُصَلِّي مَعَ رَسُولِ اللهِ ﷺ فِي غَزْوَةٍ إِذْ تَبَسَّمَ فِي صَلَاتِهِ فَلَمَّا قَضَى صَلَاتَهُ قُلْنَا يَا رَسُولَ اللهِ رَأَيْنَاكَ تَبَسَّمْتَ قَالَ مَرَّ بِي مِيكَائِيلُ وَعَلَى جَنَاحِهِ أَثَرُ غُبَارٍ وَهُوَ رَاجِعٌ مِنْ طَلَبِ الْقَوْمِ فَضَحِكَ إِلَيَّ فَتَبَسَّمْتُ إِلَيْهِ الْوَازِعُ بْنُ نَافِعٍ الْعُقَيْلِيُّ الْجَزَرِيُّ تَكَلَّمُوا فِيهِ وَقَدْ حَكَاهُ الْوَاقِدِيُّ فِي الْمَغَازِي وَقَدْ رُوِّينَا فِي كِتَابِ الطَّهَارَةِ عَنْ أَبِي سُفْيَانَ عَنْ جَابِرٍ فِي مَنْ ضَحِكَ فِي الصَّلَاةِ يُعِيدُ الصَّلَاةَ وَلَا يُعِيدُ الْوُضُوءَ وَرُوِّينَا عَنْ أَبِي مُوسَى الْأَشْعَرِيِّ أَنَّهُ قَالَ فِي قِصَّةٍ مَحْكِيَّةٍ عَنْهُ مَنْ كَانَ ضَحِكَ مِنْكُمْ فَلْيُعِدِ الصَّلَاةَ وَيُذْكَرُ مِثْلُ ذَلِكَ عَنِ ابْنِ مَسْعُودٍ