٣ـ 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.’” 