Chapter on the Virtue of Mosques and Prayer Within Them, and the Virtue of Congregational Prayer and Its Rulings

Al-Husayn ibn Sa'id from Ibn Abi Umayr from Salamah, the companion of al-Sabiri, from Ishaq ibn Ammar, who said: I said to Abu Abdillah عليه السلام, peace be upon him: “The prayer is established while I have already prayed.” Imam عليه السلام said: “Pray (the established prayer), and count it for what you have missed.”