Shaykh Abdul-Muhsin al-Abbaad was asked:
Is it benefited from the action of Abdullah Ibn Mas’ud (may Allah be pleased with him) with ‘Alqamah and al-Aswad, when he prayed with one [person] on the right and the other on the left, that it is allowed for people to make one row with a person on the right and left of the Imam if the place is tight, especially in Hajj?
“If the place is full and the people need to make a row on the right and left of the Imam, then there is no harm”.
[Sharh Sunan Abi Dawood no. 83]
The narration in the question is the following:
عَنْ عَبْدِ الرَّحْمَنِ بْنِ الأَسْوَدِ، عَنْ أَبِيهِ، قَالَ اسْتَأْذَنَ عَلْقَمَةُ وَالأَسْوَدُ عَلَى عَبْدِ اللَّهِ وَقَدْ كُنَّا أَطَلْنَا الْقُعُودَ عَلَى بَابِهِ فَخَرَجَتِ الْجَارِيَةُ فَاسْتَأْذَنَتْ لَهُمَا فَأَذِنَ لَهُمَا ثُمَّ قَامَ فَصَلَّى بَيْنِي وَبَيْنَهُ ثُمَّ قَالَ هَكَذَا رَأَيْتُ رَسُولَ اللَّهِ صلى الله عليه وسلم فَعَلَ
Narrated Abdullah ibn Mas’ud (may Allah be pleased with him):
Alqamah and al-Aswad sought permission from Abdullah (ibn Mas’ud) for admission, and we remained sitting at his door for a long time. A slave-girl came out and gave them permission [to enter]. He [Ibn Mas’ud] then got up and prayed [standing] between me [al-Aswad] and him [Alqamah]. He then said, “I witnessed the Messenger of Allah (ﷺ) doing similarly”.
[Saheeh Sunan Abi Dawood no. 613]
Hafidh Ibn Hajr rahimahullah mentioned: “Ibn Sireen replied to this narration saying that was due to the tightness of space as reported by at-Tahawi”
Shaikh Ibn ul-‘Uthaymeen rahimahullah said:
“The Imam comes in front of the congregants. If it is not possible due to the narrow space, then there is no harm that he is between them in the middle”
[Majmoo’ al-Fatawa wa-Rasaail (15/185)]
Faisal Ibn Abdul Qaadir Ibn Hassan