Ahmad ibn Muhammad ibn Said Ibn Uqdah narrated, saying: Ahmad ibn Muhammad ibn Yahya al-Khazimi narrated to us, who said: al-Hasan ibn al-Husayn narrated to us, who said: Ibrahim ibn Ali al-Murafiqi and Abu Ahmad Amru ibn al-Rabi al-Nasri narrated to us from Ja’far ibn Muhammad عليه السلام, peace be upon him: Imam al-Sadiq عليه السلام was asked about reciting behind the imam (of prayer). Imam عليه السلام said: “If you are behind an imam (of prayer) whom you follow and trust, then his recitation suffices you. But if you wish to recite, then recite in the parts where he recites quietly. When he recites aloud, then listen attentively. Allah سبحانه وتعالى, the Exalted, said: ‘And listen attentively so that you may receive mercy.’” (Surah Al-Aʿraf 7:204) Imam عليه السلام was then asked: “And if I do not trust him (imam of prayer), should I pray behind him and recite?” Imam عليه السلام said: “No. Pray before him or after him.” Imam عليه السلام was asked: “Shall I pray behind him and make it a supererogatory prayer?” Imam عليه السلام said: “If the supererogatory prayer were accepted, then the obligatory would have been accepted. But rather, make it a tasbih prayer (a non-obligatory act of glorification).”