Chapter on I'tikaf (spiritual Retreat)
Man Lā Yaḥḍuruh al-Faqīh|Volume 2|Book 2|Chapter 38
رَوَى ذَلِكَ، مُحَمَّدُ بْنُ سِنَانٍ عَنْ عَبْدِ اَلْأَعْلَى بْنِ أَعْيَنَ قَالَ: سَأَلْتُ أَبَا عَبْدِ اَللَّهِ عَلَيْهِ اَلسَّلاَمُ عَنْ رَجُلٍ وَطِئَ اِمْرَأَتَهُ وَ هُوَ مُعْتَكِفٌ لَيْلاً فِي شَهْرِ رَمَضَانَ قَالَ «عَلَيْهِ اَلْكَفَّارَةُ» قَالَ قُلْتُ فَإِنْ وَطِئَهَا نَهَاراً قَالَ «عَلَيْهِ كَفَّارَتَانِ ».
It is narrated by Muhammad ibn Sinan, from Abdul-A‘la ibn A‘yan, who said: "I asked Abu Abdullah عليه السلام about a man who engaged in sexual relations with his wife at night while performing i'tikaf during the Month of Ramadan. Imam عليه السلام said: 'He must pay one expiation.' I then asked: 'What if he engaged in sexual relations during the day?' Imam عليه السلام said: 'He must pay two expiations.'"
- Ṣaḥīḥ al-Faqīh