1ـ مُحَمَّدُ بْنُ يَحْيَى وَغَيْرُهُ عَنْ أَحْمَدَ بْنِ مُحَمَّدٍ عَنِ الْحُسَيْنِ بْنِ سَعِيدٍ عَنْ فَضَالَةَ عَنِ الْحُسَيْنِ بْنِ عُثْمَانَ عَنْ سَمَاعَةَ عَنْ أَبِي بَصِيرٍ قَالَ سَأَلْتُهُ عَنْ رَجُلٍ صَلَّى فَلَمْ يَدْرِ أَ فِي الثَّالِثَةِ هُوَ أَمْ فِي الرَّابِعَةِ قَالَ فَمَا ذَهَبَ وَهْمُهُ إِلَيْهِ إِنْ رَأَى أَنَّهُ فِي الثَّالِثَةِ وَفِي قَلْبِهِ مِنَ الرَّابِعَةِ شَيْ‏ءٌ سَلَّمَ بَيْنَهُ وَبَيْنَ نَفْسِهِ ثُمَّ يُصَلِّي رَكْعَتَيْنِ يَقْرَأُ فِيهِمَا بِفَاتِحَةِ الْكِتَابِ.

1. Muhammad ibn Yahya and others has narrated from Ahmad ibn Muhammad from al-Husayn ibn Sa‘id from Fadalah from al-Husayn ibn ‘Uthman from Sama‘ah from abu Basir who has said the following: “I once asked him (the Imam), ‘Alayhi al-Salam, about a man who performs Salah (prayer) but does not know if he is in the third or fourth Rak‘at. He (the Imam) said, ‘It depends on what his guessing indicates. If he according to his guess thinks it is the third or fourth he accepts it along with his soul, then performs two Rak‘at in which he reads al-Fatihah al-Kitab only.”’

2ـ وَعَنْهُ عَنْ أَحْمَدَ عَنِ الْحُسَيْنِ عَنْ فَضَالَةَ عَنِ الْحُسَيْنِ بْنِ أَبِي الْعَلاَءِ عَنْ أَبِي عَبْدِ الله (عَلَيْهِ الْسَّلام) قَالَ قَالَ إِنِ اسْتَوَى وَهْمُهُ فِي الثَّلاَثِ وَالأرْبَعِ سَلَّمَ وَصَلَّى رَكْعَتَيْنِ وَأَرْبَعَ سَجَدَاتٍ بِفَاتِحَةِ الْكِتَابِ وَهُوَ جَالِسٌ يَقْصِدُ فِي التَّشَهُّدِ.

2. It is a narration from him (narrator of previous Hadith) by Ahmad ibn al-Husayn from Fadalah from al-Husayn ibn abu al-‘Ala’ who has said the following: “Abu ‘Abd Allah, ‘Alayhi al-Salam, has said, ‘If one’s guess settles on his performing three or four Rak‘at, he says the phrase of offering greeting of peace, then performs two Rak‘at and four Sujud (prostrations) with al-Fatihah al-Kitab in a sitting position and says Tashahhud (testimonies of belief).”’

3ـ عَلِيُّ بْنُ إِبْرَاهِيمَ عَنْ أَبِيهِ وَمُحَمَّدُ بْنُ إِسْمَاعِيلَ عَنِ الْفَضْلِ بْنِ شَاذَانَ جَمِيعاً عَنْ حَمَّادِ بْنِ عِيسَى عَنْ حَرِيزٍ عَنْ زُرَارَةَ عَنْ أَحَدِهِمَا (عَلَيْهِما الْسَّلام) قَالَ قُلْتُ لَهُ مَنْ لَمْ يَدْرِ فِي أَرْبَعٍ هُوَ أَمْ فِي ثِنْتَيْنِ وَقَدْ أَحْرَزَ الثِّنْتَيْنِ قَالَ يَرْكَعُ رَكْعَتَيْنِ وَأَرْبَعَ سَجَدَاتٍ وَهُوَ قَائِمٌ بِفَاتِحَةِ الْكِتَابِ وَيَتَشَهَّدُ وَلاَ شَيْ‏ءَ عَلَيْهِ وَإِذَا لَمْ يَدْرِ فِي ثَلاَثٍ هُوَ أَوْ فِي أَرْبَعٍ وَقَدْ أَحْرَزَ الثَّلاَثَ قَامَ فَأَضَافَ إِلَيْهَا أُخْرَى وَلاَ شَيْ‏ءَ عَلَيْهِ وَلاَ يَنْقُضُ الْيَقِينَ بِالشَّكِّ وَلاَ يُدْخِلُ الشَّكَّ فِي الْيَقِينِ وَلاَ يَخْلِطُ أَحَدَهُمَا بِالآخَرِ وَلَكِنَّهُ يَنْقُضُ الشَّكَّ بِالْيَقِينِ وَيُتِمُّ عَلَى الْيَقِينِ فَيَبْنِي عَلَيْهِ وَلاَ يَعْتَدُّ بِالشَّكِّ فِي حَالٍ مِنَ الْحَالاَتِ.

3. Ali ibn Ibrahim has narrated from his father and Muhammad ibn ’Isma‘il from al-Fadl ibn Shadhan all from Hammad ibn ‘Isa from Hariz from Zurarah who has said the following: “I once asked one of the two Imam, ‘Alayhim al-Salam, about a man who performs Salah (prayer) but does not know if he is in the second or fourth Rak‘at but he knows that he has performed two Rak‘at. He (the Imam) said, ‘He performs two Rak‘at and four Sujud (prostrations). He does it in a standing position with al-Fatihah al-Kitab and Tashahhud (testimonies of belief) and he is not obligated for anything in this matter. If he does not know he is in the third or fourth and if he has secured three Rak‘at, he stands up to perform one more Rak‘at and he is not obligated for anything in this matter. He does not destroy his certainty with doubt and doubt does not enter into certainty. No one of them mixes with the other but doubt is destroyed by certainty and he completes with certainty, based on certainty and does not depend on doubt in no condition whatsoever.’”

4ـ عَلِيُّ بْنُ إِبْرَاهِيمَ عَنْ مُحَمَّدِ بْنِ عِيسَى عَنْ يُونُسَ عَنِ ابْنِ مُسْكَانَ عَنِ ابْنِ أَبِي يَعْفُورٍ قَالَ سَأَلْتُ أَبَا عَبْدِ الله (عَلَيْهِ الْسَّلام) عَنِ الرَّجُلِ لاَ يَدْرِي رَكْعَتَيْنِ صَلَّى أَمْ أَرْبَعاً قَالَ يَتَشَهَّدُ وَيُسَلِّمُ ثُمَّ يَقُومُ فَيُصَلِّي رَكْعَتَيْنِ وَأَرْبَعَ سَجَدَاتٍ يَقْرَأُ فِيهِمَا بِفَاتِحَةِ الْكِتَابِ ثُمَّ يَتَشَهَّدُ وَيُسَلِّمُ وَإِنْ كَانَ صَلَّى أَرْبَعاً كَانَتْ هَاتَانِ نَافِلَةً وَإِنْ كَانَ صَلَّى رَكْعَتَيْنِ كَانَتْ هَاتَانِ تَمَامَ الأرْبَعِ وَإِنْ تَكَلَّمَ فَلْيَسْجُدْ سَجْدَتَيِ السَّهْوِ.

4. Ali ibn Ibrahim has narrated from Muhammad ibn ’Isma‘il from Yunus from ibn Muskan from ibn abu Ya‘fur who has said the following: “I once asked abu ‘Abd Allah, ‘Alayhi al-Salam, about a man who does not know if he has performed two Rak‘at or four. He (the Imam) said, ‘He says Tashahhud (testimonies of belief) and the phrase of offering greeting of peace, then stands up to perform two Rak‘at and four Sujud (prostrations) in which he reads al-Fatihah al-Kitab, thereafter says Tashahhud (testimonies of belief) and the phrase of offering greeting of peace. If he has, in fact, performed four Rak‘at, the two Rak‘at are optional; but if they were two Rak‘at, then these two Rak‘at complete the four, and if he has spoken something other than what is part of Salah (prayer) he performs two Sajdah (prostrations) because of mistake.’”

5ـ حَمَّادٌ عَنْ حَرِيزٍ عَنْ مُحَمَّدِ بْنِ مُسْلِمٍ قَالَ إِنَّمَا السَّهْوُ مَا بَيْنَ الثَّلاَثِ وَالأرْبَعِ وَ فِي الاثْنَتَيْنِ وَفِي الأرْبَعِ بِتِلْكَ الْمَنْزِلَةِ وَمَنْ سَهَا وَلَمْ يَدْرِ ثَلاَثاً صَلَّى أَمْ أَرْبَعاً وَاعْتَدَلَ شَكُّهُ قَالَ يَقُومُ فَيُتِمُّ ثُمَّ يَجْلِسُ فَيَتَشَهَّدُ وَيُسَلِّمُ وَيُصَلِّي رَكْعَتَيْنِ وَأَرْبَعَ سَجَدَاتٍ وَهُوَ جَالِسٌ فَإِنْ كَانَ أَكْثَرُ وَهْمِهِ إِلَى الأرْبَعِ تَشَهَّدَ وَسَلَّمَ ثُمَّ قَرَأَ فَاتِحَةَ الْكِتَابِ وَرَكَعَ وَسَجَدَ ثُمَّ قَرَأَ وَسَجَدَ سَجْدَتَيْنِ وَتَشَهَّدَ وَسَلَّمَ وَإِنْ كَانَ أَكْثَرُ وَهْمِهِ إِلَى الثِّنْتَيْنِ نَهَضَ فَصَلَّى رَكْعَتَيْنِ وَتَشَهَّدَ وَسَلَّمَ.

5. Hammad has narrated from Hariz from Muhammad ibn Muslim who has said the following: “He (the Imam), ‘Alayhi al-Salam, has said, ‘The case of doubt whether it is three or four or if it is two or four is of the same position. If one doubts and does not know if he has performed three or four and his doubt about both sides are equal’, he (the Imam) said, ‘Such person stands up and completes (Salah (prayer)). He then sits down, says Tashahhud (testimonies of belief) and the phrase of offering greeting of peace then performs two Rak’ah and four Sujud (prostrations) in a sitting position. If his doubt has a greater side toward four, he says Tashahhud (testimonies of belief) and the phrase of offering greeting of peace then reads al-Fatihah al-Kitab and performs Ruku’ (bowing down on one’s knees) and Sajdah (prostration) then reads and performs two Sajdah (prostration), says Tashahhud (testimonies of belief) and the phrase of offering greeting of peace. If the greater side of his doubt is toward two Rak’ah, he stands up, performs two Rak’ah, says Tashahhud (testimonies of belief) and the phrase of offering greeting of peace.’”

6ـ عَلِيُّ بْنُ إِبْرَاهِيمَ عَنْ أَبِيهِ عَنِ ابْنِ أَبِي عُمَيْرٍ عَنْ بَعْضِ أَصْحَابِهِ عَنْ أَبِي عَبْدِ الله (عَلَيْهِ الْسَّلام) فِي رَجُلٍ صَلَّى فَلَمْ يَدْرِ أَ ثِنْتَيْنِ صَلَّى أَمْ ثَلاَثاً أَمْ أَرْبَعاً قَالَ يَقُومُ فَيُصَلِّي رَكْعَتَيْنِ مِنْ قِيَامٍ وَيُسَلِّمُ ثُمَّ يُصَلِّي رَكْعَتَيْنِ مِنْ جُلُوسٍ وَيُسَلِّمُ فَإِنْ كَانَتْ أَرْبَعَ رَكَعَاتٍ كَانَتِ الرَّكْعَتَانِ نَافِلَةً وَإِلاَّ تَمَّتِ الأرْبَعُ.

6. Ali ibn Ibrahim has narrated from his father from ibn abu ‘Umayr from certain persons of his people who has said the following: “Abu ‘Abdullah, ‘Alayhi al-Salam, about the case of one who performs Salah (prayer) and doubts if he has performed two or four Rak’ah, has said, ‘ He stands up and performs two Rak’ah in a standing position. He then says the phrase of offering greeting of peace, then performs two Rak’ah in a sitting position, and says the phrase of offering greeting of peace. If, in fact, they were four Rak’ah the two Rak’ah become optional; otherwise, they complete the four Rak’ah.’”

7ـ مُحَمَّدُ بْنُ يَحْيَى عَنْ أَحْمَدَ بْنِ مُحَمَّدٍ عَنِ الْحُسَيْنِ بْنِ سَعِيدٍ عَنْ فَضَالَةَ بْنِ أَيُّوبَ عَنْ أَبَانٍ عَنْ عَبْدِ الرَّحْمَنِ بْنِ سَيَابَةَ وَأَبِي الْعَبَّاسِ عَنْ أَبِي عَبْدِ الله (عَلَيْهِ الْسَّلام) قَالَ إِذَا لَمْ تَدْرِ ثَلاَثاً صَلَّيْتَ أَوْ أَرْبَعاً وَوَقَعَ رَأْيُكَ عَلَى الثَّلاَثِ فَابْنِ عَلَى الثَّلاَثِ وَإِنْ وَقَعَ رَأْيُكَ عَلَى الأرْبَعِ فَسَلِّمْ وَانْصَرِفْ وَإِنِ اعْتَدَلَ وَهْمُكَ فَانْصَرِفْ وَصَلِّ رَكْعَتَيْنِ وَأَنْتَ جَالِسٌ.

7. Muhammad ibn Yahya has narrated from Ahmad ibn Muhammad from af-Husayn ibn Sa‘id from Fadalah ibn Ayyub from Aban from ‘Abd al-Rahman ibn Sayabah and abu al-‘Abbas who has said the following: “Abu ‘Abdullah, ‘Alayhi al-Salam, has said, ‘If you do not know whether you have performed three or four Rak’ah and your thought settles on three, then consider it three. If your thought settles on four, say Salam (the phrase of offering greeting of peace) and end Salah (prayer). If your guess is equal; end Salah (prayer), then perform two Rak’ah in a sitting position.’”

8ـ عَلِيُّ بْنُ إِبْرَاهِيمَ عَنْ أَبِيهِ عَنِ ابْنِ أَبِي عُمَيْرٍ عَنْ حَمَّادِ بْنِ عُثْمَانَ عَنِ الْحَلَبِيِّ عَنْ أَبِي عَبْدِ الله (عَلَيْهِ الْسَّلام) قَالَ إِذَا لَمْ تَدْرِ ثِنْتَيْنِ صَلَّيْتَ أَمْ أَرْبَعاً وَلَمْ يَذْهَبْ وَهْمُكَ إِلَى شَيْ‏ءٍ فَتَشَهَّدْ وَسَلِّمْ ثُمَّ صَلِّ رَكْعَتَيْنِ وَأَرْبَعَ سَجَدَاتٍ تَقْرَأُ فِيهِمَا بِأُمِّ الْقُرْآنِ ثُمَّ تَشَهَّدْ وَسَلِّمْ فَإِنْ كُنْتَ إِنَّمَا صَلَّيْتَ رَكْعَتَيْنِ كَانَتَا هَاتَانِ تَمَامَ الأرْبَعِ وَإِنْ كُنْتَ صَلَّيْتَ أَرْبَعاً كَانَتَا هَاتَانِ نَافِلَةً وَإِنْ كُنْتَ لاَ تَدْرِي ثَلاَثاً صَلَّيْتَ أَمْ أَرْبَعاً وَلَمْ يَذْهَبْ وَهْمُكَ إِلَى شَيْ‏ءٍ فَسَلِّمْ ثُمَّ صَلِّ رَكْعَتَيْنِ وَأَنْتَ جَالِسٌ تَقْرَأُ فِيهِمَا بِأُمِّ الْكِتَابِ وَإِنْ ذَهَبَ وَهْمُكَ إِلَى الثَّلاَثِ فَقُمْ فَصَلِّ الرَّكْعَةَ الرَّابِعَةَ وَلاَ تَسْجُدْ سَجْدَتَيِ السَّهْوِ فَإِنْ ذَهَبَ وَهْمُكَ إِلَى الأرْبَعِ فَتَشَهَّدْ وَسَلِّمْ ثُمَّ اسْجُدْ سَجْدَتَيِ السَّهْوِ.

8. Ali ibn Ibrahim has narrated from his father from ibn abu ‘Umayr from Hammad ibn ‘Uthman from al-Halabiy who has said the following: “Abu ‘Abdullah, ‘Alayhi al-Salam, has said, ‘ You may not know whether you have performed two or four Rak’ah and your guess about one side is not greater than the other side. You must say Tashahhud (testimonies of belief) and Salam (the phrase of offering greeting of peace), then perform two Rak’ah and four Sujud (prostrations). Read in them ‘ Umm al-Quran, then say Tashahhud (testimonies of belief) and Salam (the phrase of offering greeting of peace). If, in fact, you had performed two Rak’ah these two complete the four and if, in fact, you had performed four, these two become optional. If you do not know whether you have performed three or four Rak’ah and your guess about one side is not greater than the other; say Salam (the phrase of offering greeting of peace), then perform two Rak’ah in a sitting position. Read in them al-Fatihah al-Kitab. If your guess about three is greater, then perform the fourth Rak’ah. Do not perform two Sajdah (prostration) because of mistake. If your guess about four is greater; say Tashahhud (testimonies of belief) and Salam (the phrase of offering greeting of peace) then perform two Sajdah (prostration) because of mistake.’”

9ـ مُحَمَّدُ بْنُ يَحْيَى عَنْ أَحْمَدَ بْنِ مُحَمَّدٍ عَنْ عَلِيِّ بْنِ حَدِيدٍ عَنْ جَمِيلٍ عَنْ بَعْضِ أَصْحَابِنَا عَنْ أَبِي عَبْدِ الله (عَلَيْهِ الْسَّلام) قَالَ فِي مَنْ لاَ يَدْرِي أَ ثَلاَثاً صَلَّى أَمْ أَرْبَعاً وَوَهْمُهُ فِي ذَلِكَ سَوَاءٌ قَالَ فَقَالَ إِذَا اعْتَدَلَ الْوَهْمُ فِي الثَّلاَثِ وَالأرْبَعِ فَهُوَ بِالْخِيَارِ إِنْ شَاءَ صَلَّى رَكْعَةً وَهُوَ قَائِمٌ وَإِنْ شَاءَ صَلَّى رَكْعَتَيْنِ وَأَرْبَعَ سَجَدَاتٍ وَهُوَ جَالِسٌ وَقَالَ فِي رَجُلٍ لَمْ يَدْرِ أَ ثِنْتَيْنِ صَلَّى أَمْ أَرْبَعاً وَوَهْمُهُ يَذْهَبُ إِلَى الأرْبَعِ أَوْ إِلَى الرَّكْعَتَيْنِ فَقَالَ يُصَلِّي رَكْعَتَيْنِ وَأَرْبَعَ سَجَدَاتٍ وَقَالَ إِنْ ذَهَبَ وَهْمُكَ إِلَى رَكْعَتَيْنِ وَأَرْبَعٍ فَهُوَ سَوَاءٌ وَلَيْسَ الْوَهْمُ فِي هَذَا الْمَوْضِعِ مِثْلَهُ فِي الثَّلاَثِ وَالأرْبَعِ.

9. Muhammad ibn Yahya has narrated from Ahmad ibn Muhammad from Ali ibn Hadid from Jamil certain persons of our people who have said the following: “Abu ‘Abdullah, ‘Alayhi al-Salam, has said, ‘ One may not know whether he has performed three or four and his guess about both sides is equal. (For such case) he (the narrator) has said that he (the Imam) said, ‘If his guess is equal about three and four, he has the choice to perform one Rak’ah standing or two Rak’ah in a sitting position and four Sujud (prostrations) in a sitting position.’ He (the Imam), ‘Alayhi al-Salam, about a man who does not know if he has performed two or four Rak’ah and his guess about four is greater or about two Rak‘at, he (the Imam) said that he performs two Rak‘at and four Sujud (prostrations). He (the Imam) said, ‘If your guess about two Rak‘at and four is equal, then this and the case of doubt about whether it is three or four Rak‘at is not the same.”’