Imâm Al-Bukhârî reports in his Sahîh, in the chapter entitled The virtue of one who prays [at night] in Ramadân, from ‘Abd Al-Rahmân b. ‘Abdin Al-Qârî:

I went out to the mosque with ‘Umar b. Al-Khattâb one night in Ramadân, and we found people in separate groups: some men praying by themselves and others praying with a small group behind them. ‘Umar said, “I think if I gathered them behind one reciter it would be better.” Later, he made up his mind and gathered them behind Ubay b. Ka’b. On another night, I went out with him again and the people were praying behind their reciter [Ubay]. ‘Umar said, “What a good innovation (bid’ah) this is, but what they are missing by sleeping is better than what they are staying up to pray.” He meant the last part of the night, for the people used to pray in the early part.

This is further clarified by the more detailed report in Ibn Sa’d’s Al-Tabaqât Al-Kubrâ Vol.5 p42 from Nawfal b. Iyâs Al-Hudhalî:

During the time of ‘Umar b. Al-Khattâb, we used to pray in Ramadân in groups – here and there – in the mosque. People would incline to pray behind those who had the best voices. ‘Umar said, “Do I not see that they are treating the Qurân like song? By Allâh, if I can, I will change this.” Only three nights later, he told Ubay b. Ka’b to lead them in prayer, then stood behind the rows and said, “If this is a bid’ah, then what a good bid’ah it is.”

Al-‘Allâmah Al-Mu’allimî Al-Yamânî graded this narration’s chain of transmission sahîh in his treatise Qiyâmu Ramadân p51.

Points to note

• We are reminded through this narration to avoid falling into the same problems that ‘Umar sought to solve by appointing a single imâm during his Caliphate:
  • The appearance of splitting and schism, which Islam disapproves of
  • Distracting each other by reciting audibly at the same time in the mosque, reciting over each other
  • Preferring imâms and reciters for having nice voices even though others may know more Qurân and be more qualified to lead
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• Scholars point out that the statement ‘what a good bid’ah this is’ does not affirm that there is any such thing as a good bid’ah in a religious sense, because innovation in religion is unconditionally and unequivocally blameworthy in the texts of hadîth and countless statements of the Salaf. This statement is therefore taken to mean that ‘Umar meant that what he saw was a good development – a bid’ah in the linguistic sense of something new – relative to the situation before he appointed a single imâm. This meaning is also clear from the fact that night prayer in congregation in Ramadân already has a precedent from Allâh’s Messenger – Allâh’s peace and blessings be upon him.
• Having said that, the report in Ibn Sa’d, ‘if this is a bid’ah, then what a good bid’ah it is’ evidences that ‘Umar never called it a bid’ah in the first place, but was being rhetorical, as suggested by Shaykh Al-Mu’allimî in Qiyâm Ramadân, in the same way as intended in Sûrah Al-Zukhruf, verse 81, “Say, if Al-Rahmân has a son, then I am the first of the worshippers.’”

And Allâh knows best.