What was narrated by al-Husayn ibn Sa’id from Fadalah from Hammad ibn Uthman, who said:
I said to Abu Abdillah عليه السلام: "I am in prostration and I doubt, did I bow or not?" Imam عليه السلام said: "Continue (with your prayer)."
Ali Akbar al-Ghaffari
Tahdhīb al-Aḥkām fī Sharḥ al-Muqniʿah, vol. 2, p. 160
