Chapter on the Rulings of Congregational Prayer (the Minimum Number for Congregational Prayer, the Description of the Imam, Who Is to Be Followed and Who Is Not to Be Followed, Recitation Behind Both of Them, the Rulings of Those Led in Prayer, and Other Such Rulings Related to It)

Muhammad ibn Yaqub narrated from Muhammad ibn Ismail, from al-Fadl ibn Shadhan, from Ibn Abi Umayr, from Muawiyah ibn Ammar, who said: I asked Abu Abdillah عليه السلام, peace be upon him, about a man who comes to the mosque while they are already in prayer, and the imam (of prayer) has preceded him by a rak’ah or more. Then the imam (of prayer) becomes unable to continue, so he takes the hand of that man who is the nearest of the people to him and places him forward. Imam عليه السلام said: “He should complete the prayer with the people, then sit. And when they finish the tashahhud, he should gesture with his hand to them to the right and to the left and that gesture with his hand to them is (considered) the taslim and conclusion of their prayer. Then he should complete what had passed or remained upon him.”