Congregational Prayer and Its Virtue
Man Lā Yaḥḍuruh al-Faqīh|Volume 1|Book 1|Chapter 57
وَقَالَ لَهُ أَيْضاً: إِنَّ عَلَى بَابِي مَسْجِداً يَكُونُ فِيهِ قَوْمٌ مُخَالِفُونَ مُعَانِدُونَ فَهُمْ يُمْسُونَ فِي اَلصَّلاَةِ وَ أَنَا أُصَلِّي اَلْعَصْرَ ثُمَّ أَخْرُجُ فَأُصَلِّي مَعَهُمْ فَقَالَ «أَ مَا تَرْضَى أَنْ تُحْسَبَ لَكَ، بِأَرْبَعٍ وَ عِشْرِينَ صَلاَةً.
He also said to Imam عليه السلام: "There is a mosque near my door in which there are people who oppose and are hostile. They remain in prayer during the evening, and I pray Asr and then go out and join them in prayer." Imam عليه السلام said: "Would you not be pleased to have it counted for you as twenty-four prayers?".
- Ṣaḥīḥ al-Faqīh