Sahl ibn Ziyad from Ahmad ibn Muhammad ibn Abi Nasr from al-Mithami from Ishaq ibn Yazid who said: I said to Abu Abdillah عليه السلام, peace be upon him: “May I be your ransom, the imam (of prayer) precedes me by one rak‘ah, so I have one and he has two. Should I recite the tashahhud every time I sit?” Imam عليه السلام said: “Yes, indeed the tashahhud is a blessing.”