Congregational Prayer and Its Virtue
Man Lā Yaḥḍuruh al-Faqīh|Volume 1|Book 1|Chapter 57
وَ رَوَى عَنْهُ حَفْصُ بْنُ اَلْبَخْتَرِيُّ أَنَّهُ قَالَ: «يُحْسَبُ لَكَ إِذَا دَخَلْتَ مَعَهُمْ وَ إِنْ كُنْتَ لاَ تَقْتَدِي بِهِمْ حُسِبَ لَكَ مِثْلُ مَا يُحْسَبُ لَكَ إِذَا كُنْتَ مَعَ مَنْ تَقْتَدِي بِهِ.
It is narrated from him by Hafs ibn al-Bakhtari that Imam عليه السلام said: "It will be counted for you when you join them (in prayer), even if you do not follow them (in intention); it will be counted for you just as it would if you were with someone you follow”.
- Ṣaḥīḥ al-Faqīh