Chapter on the Description of Ablution (Wudu)
Tahdhīb al-Aḥkām|Volume 1|Book 1|Chapter 4
اَلْحُسَيْنُ بْنُ سَعِيدٍ عَنْ فَضَالَةَ عَنْ أَبَانِ بْنِ عُثْمَانَ عَنْ بُكَيْرِ بْنِ أَعْيَنَ قَالَ: قُلْتُ لَهُ اَلرَّجُلُ يَشُكُّ بَعْدَ مَا يَتَوَضَّأُ قَالَ «هُوَ حِينَ يَتَوَضَّأُ أَذْكَرُ مِنْهُ حِينَ يَشُكُّ».
Al-Husayn ibn Sa'id narrated from Fadala, from Aban ibn Uthman, from Bukayr ibn A'yan, who said:
I said to Imam عليه السلام: "A man doubts (his ablution) after performing ablution." Imam عليه السلام said: "He is more mindful at the time of performing ablution than when he later doubts (his ablution)."
- Tahdhīb al-Aḥkām fī Sharḥ al-Muqniʿah, vol. 1, p. 104
- Ṣaḥīḥ al-Tahdhīb, p. 58