Al-Kāfi

Hadith 1280
congregational-prayerprayer-etiquette
5ـ عَلِيُّ بْنُ إِبْرَاهِيمَ عَنْ أَبِيهِ عَنِ ابْنِ أَبِي عُمَيْرٍ عَنْ حَفْصِ بْنِ الْبَخْتَرِيِّ عَنْ أَبِي عَبْدِ الله (عَلَيْهِ الْسَّلام) قَالَ يَنْبَغِي لِلإِمَامِ أَنْ يُسْمِعَ مَنْ خَلْفَهُ التَّشَهُّدَ وَلاَ يُسْمِعُونَهُ هُمْ شَيْئاً.
5. Ali ibn Ibrahim has narrated from his father from Ibn Abi ‘Umayr from Hafs ibn al-Bakhtariy who has said the following: “Abu ‘Abd Allah (a.s.), has said, ‘It is proper for the Imam to make people behind him hear Tashahhud (testimonies of belief) and they must not make him to hear anything from them.’”
Source: Shaykh Muḥammad b. Yaʿqūb al-Kulaynī