Chapter on the Description of Ablution (Wudu)
Tahdhīb al-Aḥkām|Volume 1|Book 1|Chapter 4
عَنْهُ عَنْ ابْنِ أَبِي عُمَيْرٍ عَنْ أَبِي أَيُّوبَ عَنْ مُحَمَّدِ بْنِ مُسْلِمٍ قَالَ: قُلْتُ لِأَبِي عَبْدِ اللَّهِ عَلَيْهِ السَّلَامُ: رَجُلٌ يَشُكُّ فِي الْوُضُوءِ بَعْدَ مَا فَرَغَ مِنَ الصَّلَاةِ؟ قَالَ: يَمْضِي عَلَى صَلَاتِهِ وَلَا يُعِيدُ.
From him, from Ibn Abi Umayr, from Abu Ayyub, from Muhammad ibn Muslim, who said:
I said to Abu Abdullah عليه السلام: "A man doubts his ablution after he has finished the prayer?" Imam عليه السلام said: "He continues with his prayer and does not repeat it."
- Tahdhīb al-Aḥkām fī Sharḥ al-Muqniʿah, vol. 1, p. 106
- Ṣaḥīḥ al-Tahdhīb, p. 58