Sayyiduna Anas (may Allah be pleased with him) narrates: During the blessed time of the Prophet (peace and blessings of Allah be upon him), we used to prompt our imam.

Sayyiduna Ali (may Allah be pleased with him) said: "Whoever prompts the Imam, he has spoken (i.e., his prayer will be invalidated)." The narrator of this narration, Muhammad bin Salim, is abandoned.

Sayyiduna Ali (may Allah be pleased with him) said: "This is speech." (The narrator says:) That is, prompting the Imam.

Sayyiduna Ali (may Allah be pleased with him) said: "When the imam asks you for something to eat, then feed him (i.e., prompt him if he forgets)."

Sayyiduna Ubayy bin Ka'b (may Allah be pleased with him) narrates: The Prophet (peace and blessings of Allah be upon him) was leading us in prayer, and he began to recite a surah, but he omitted one verse from it. When he finished the prayer, I said: O Messenger of Allah! Has such-and-such verse been abrogated? The Prophet (peace and blessings of Allah be upon him) said: "No." I said: You did not recite it. The Prophet (peace and blessings of Allah be upon him) said: "Why did you not prompt me?"

Sayyiduna Anas (may Allah be pleased with him) narrates: The companions of the Prophet (peace and blessings be upon him) used to prompt each other during prayer.