Chapter on Etiquettes of Causes Requiring Purification
Tahdhīb al-Aḥkām|Volume 1|Book 1|Chapter 3
فَأَمَّا مَا رَوَاهُ اَلصَّفَّارُ عَنْ مُحَمَّدِ بْنِ عِيسَى قَالَ: كَتَبَ إِلَيْهِ رَجُلٌ هَلْ يَجِبُ اَلْوُضُوءُ مِمَّا خَرَجَ مِنَ اَلذَّكَرِ بَعْدَ اَلاِسْتِبْرَاءِ فَكَتَبَ« نَعَمْ».
As for what was narrated by Al-Saffar from Muhammad bin Isa, who said:
(Narrator said) "A man wrote to Imam عليه السلام asking: 'Is it obligatory to perform wudu for what exits from the penis after istibra?' Imam عليه السلام wrote: 'Yes.'"
- Tahdhīb al-Aḥkām fī Sharḥ al-Muqniʿah, vol. 1, p. 29
- Ṣaḥīḥ al-Tahdhīb