Chapter on the Prayer Times (Mawaqit)
Tahdhīb al-Aḥkām|Volume 2|Book 1|Chapter 13
عَلِيٌّ عَنْ أَبِيهِ عَنْ حَمَّادٍ عَنْ حَرِيزٍ عَنْ زُرَارَةَ وَ اَلْفُضَيْلِ عَنْ أَبِي جَعْفَرٍ عَلَيْهِ اَلسَّلاَمُ أَنَّهُ قَالَ:« مَتَى مَا اِسْتَيْقَنْتَ أَوْ شَكَكْتَ فِي وَقْتِ صَلاَةٍ أَنَّكَ لَمْ تُصَلِّهَا أَوْ فِي وَقْتِ فَوْتِهَا صَلَّيْتَهَا فَإِنْ شَكَكْتَ بَعْدَمَا خَرَجَ وَقْتُ اَلْفَوْتِ فَقَدْ دَخَلَ حَائِلٌ فَلاَ إِعَادَةَ عَلَيْكَ مِنْ شَكٍّ حَتَّى تَسْتَيْقِنَ فَإِنِ اِسْتَيْقَنْتَ فَعَلَيْكَ إِعَادَةُ أَنْ تُصَلِّيَهَا فِي أَيِّ حَالٍ كُنْتَ»
Ali from his father from Hammad from Hariz from Zurarah and Al-Fudhayl:
Abu Ja’far عليه السلام, peace be upon him, said: "Whenever you become certain or you doubt within the time of the prayer that you have not prayed it, or within the time of its expiration you pray it. But if you doubt after the time of expiration has passed, then a barrier has entered, and there is no re-praying upon you due to doubt unless you become certain. If you become certain, then it is upon you to re-pray it, no matter what state you are in."
- Tahdhīb al-Aḥkām fī Sharḥ al-Muqniʿah, vol. 2, p. 297
- Ṣaḥīḥ al-Tahdhīb