Arabic (Original)
حَدَّثَنَا عَلِيُّ بْنُ عَيَّاشٍ حَدَّثَنَا مُحَمَّدُ بْنُ مُطَرِّفٍ حَدَّثَنَا زَيْدُ بْنُ أَسْلَمَ عَنْ عَطَاءِ بْنِ يَسَارٍ عَنْ أَبِي سَعِيدٍ الْخُدْرِيِّ قَالَ قَالَ النَّبِيُّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ إِذَا شَكَّ أَحَدُكُمْ فِي صَلَاتِهِ فَلْيُلْقِ الشَّكَّ وَلْيَبْنِ عَلَى الْيَقِينِ وَلْيُصَلِّ سَجْدَتَيْنِ فَإِنْ كَانَتْ خَمْسًا شَفَعَ بِهِمَا وَإِنْ كَانَ صَلَّى أَرْبَعًا كَانَتَا تَرْغِيمًا لِلشَّيْطَانِ.
English Translation
Ali ibn Ayyash told us, Muhammad ibn Mutarrif told us, Zayd ibn Aslam told us, from Ata' ibn Yasar, from Abu Sa'id al-Khudri, who said: The Prophet, peace and blessings be upon him, said: "If one of you doubts in his prayer, let him discard the doubt and build upon certainty, and prostrate twice. If it was five, they make it even; and if he had prayed four, they will be a humiliation for Satan."