Arabic (Original)
حَدَّثَنَا إِبْرَاهِيمُ بْنُ سَعْدٍ حَدَّثَنِي مُحَمَّدُ بْنُ إِسْحَاقَ عَنْ مَكْحُولٍ عَنْ كُرَيْبٍ عَنِ ابْنِ عَبَّاسٍ أَنَّهُ قَالَ لَهُ عُمَرُ يَا غُلَامُ هَلْ سَمِعْتَ مِنْ رَسُولِ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ أَوْ مِنْ أَحَدٍ مِنْ أَصْحَابِهِ إِذَا شَكَّ الرَّجُلُ فِي صَلَاتِهِ مَاذَا يَصْنَعُ قَالَ فَبَيْنَا هُوَ كَذَلِكَ إِذْ أَقْبَلَ عَبْدُ الرَّحْمَنِ بْنُ عَوْفٍ فَقَالَ فِيمَ أَنْتُمَا فَقَالَ عُمَرُ سَأَلْتُ هَذَا الْغُلَامَ هَلْ سَمِعْتَ مِنْ رَسُولِ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ أَوْ أَحَدٍ مِنْ أَصْحَابِهِ إِذَا شَكَّ الرَّجُلُ فِي صَلَاتِهِ مَاذَا يَصْنَعُ فَقَالَ عَبْدُ الرَّحْمَنِ سَمِعْتُ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ يَقُولُ إِذَا شَكَّ أَحَدُكُمْ فِي صَلَاتِهِ فَلَمْ يَدْرِ أَوَاحِدَةً صَلَّى أَمْ ثِنْتَيْنِ فَلْيَجْعَلْهَا وَاحِدَةً وَإِذَا لَمْ يَدْرِ ثِنْتَيْنِ صَلَّى أَمْ ثَلَاثًا فَلْيَجْعَلْهَا ثِنْتَيْنِ وَإِذَا لَمْ يَدْرِ أَثَلَاثًا صَلَّى أَمْ أَرْبَعًا فَلْيَجْعَلْهَا ثَلَاثًا ثُمَّ يَسْجُدْ إِذَا فَرَغَ مِنْ صَلَاتِهِ وَهُوَ جَالِسٌ قَبْلَ أَنْ يُسَلِّمَ سَجْدَتَيْنِ.
English Translation
Umar said to Ibn Abbas: 'O boy, have you heard from the Messenger of Allah (peace be upon him) or from any of his Companions what a man should do when he has doubt in his prayer?' While they were discussing, Abd al-Rahman ibn Awf came and asked what they were talking about. Umar explained. Abd al-Rahman said: 'I heard the Messenger of Allah (peace be upon him) say: When any of you has doubt in his prayer and does not know whether he prayed one or two rak'ahs, let him count it as one. If he does not know whether he prayed two or three, let him count it as two. If he does not know whether he prayed three or four, let him count it as three. Then let him prostrate two prostrations while sitting, after finishing his prayer, before giving the taslim.'