What is the ruling on having multiple congregations in a mosque that has a regular imam?

The questioner : The repetition of the second congregational prayer, the repetition of the second congregation?

The Shaykh : Yes, the second congregation.
And upon you be peace and Allah's mercy and blessings.
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The Shaykh : Come forward, our brothers, come forward, jostle with one another, show mercy to one another.

Eid Abbasi : Because of the recording...

The Shaykh : The second congregational prayer and any subsequent congregations held after the first congregation is a matter of scholarly disagreement among the four schools of jurisprudence, as is well known today. Abu Hanifa, Imam Malik, and Imam Ahmad—pardon me; Imam Abu Hanifa, Imam Malik, and Imam al-Shafi'i—these three hold the view that the second congregation and any subsequent ones are not prescribed. As for Imam Ahmad, the well-known view attributed to him in the books of his students and followers is that this second congregation is prescribed. They cite as evidence the generality of his saying (peace and blessings be upon him): , or in another narration: . I found another narration from Imam Ahmad in the book known as "Masail Abi Dawud" from him. This other narration aligns with what we mentioned regarding the school of the three imams; Imam Ahmad said, in response to a question from Imam Abu Dawud: "Repeating the congregation in the Sacred Mosque and the Prophet's Mosque is more disliked." We understood from the superlative form in his wording that repeating the congregation in mosques in general is disliked, but it is more disliked in the two greatest mosques, Mecca and Medina.
Thus, Imam Ahmad aligns in this authentic narration from him with the schools of the three imams. Based on this, we can say: The four imams agreed on the dislike of repeating the congregation in the same mosque. However, this ruling is not absolute; rather, it is specific to a mosque described as having a regular imam and a regular mu'adhdhin. It is in this mosque, which has a regular imam and a regular mu'adhdhin, that the prayer is disliked. Imam al-Shafi'i detailed this in his great book known as "Al-Umm." He said there in clear Arabic: "If a group enters the mosque and finds that the imam has already prayed, they should pray individually. If they pray in congregation, it suffices them, but I dislike that for them because it was not the practice of the Salaf."

The questioner: Peace be upon you.

The Shaykh : And upon you be peace, and the mercy of Allah and His blessings.
This is the statement of Imam al-Shafi'i, in which he explicitly states that if a group enters the mosque and finds that the official imam has finished the prayer, they should pray individually. He clarifies that the reason for this ruling is that establishing a second congregation after the regular imam is a religious innovation that the righteous Salaf did not know. However, I return to say: If they pray in congregation despite this, their prayer is not invalid; rather, it is disliked because they opposed the way of the Salaf. Then he says: "This applies to a mosque that has a regular imam and a regular mu'adhdhin. As for a mosque on the side of the road that has no regular imam and no regular mu'adhdhin, whenever a group comes, they pray in congregation there; there is nothing wrong with that, because it does not contain the meaning I mentioned."
What supports this ruling—that is, the dislike of repeating the prayer in the second congregation in a mosque that has a regular imam and a regular mu'adhdhin—is what Imam al-Tabarani narrated in "Al-Mu'jam al-Kabir" with a good chain of narration. Two of his companions visited him at his house, then he went out to the mosque with them to pray. He found that people had finished their prayer and were leaving the mosque. So he returned them to his house and prayed with them in congregation. If repeating the congregation in the mosque had been a prescribed matter, Ibn Mas'ud would not have returned with his obligatory prayer to his house with them; because we all know that the mosque was built for the obligatory prayers, as he (peace and blessings be upon him) said: , and in another narration: . Since that is the case, Ibn Mas'ud could have continued his way to the mosque instead of returning to his house, and prayed with them in congregation. When we see that he did not do so, but rather prayed the congregation in his house, we understood from his action that it is a basis and evidence for those imams who said: Repeating the congregation in the mosque... is a religious innovation that is not from the practice of the Salaf. This confirms the statement of Imam al-Shafi'i. This is what is recorded in the depths of the books.