Mishkat al-Masabih 972
Al-Azraq b. Qais said that an imam, of theirs whose kunya was Abu Rimtha led them in prayer and said:
I prayed this prayer, or one like it, along with God’s Messenger. Abu Bakr and ‘Umar were standing in the front row on his right, and there was a man who had been present at the first takbira in the prayer. God’s Prophet prayed the prayer, then gave the salutation to his right and his left so that we saw the whiteness of his cheeks, then turned away as Abu Rimtha (meaning himself) has done. The man who had been present with him at the first takbira in the prayer then got up to pray another prayer, whereupon ‘Umar leaped up, and seizing him by the shoulders, shook him and said, “Sit down, for the People of the Book will perish for no other reason than that there was no interval between their prayers.” The Prophet raised his eyes and said, “God has made you say what is right, son of al-Khattab.” 

Abu Dawud transmitted it.
عَنِ الْأَزْرَقِ بْنِ قَيْسٍ قَالَ: صَلَّى بِنَا إِمَامٌ لَنَا يُكْنَى أَبَا رِمْثَةَ قَالَ صَلَّيْتُ هَذِهِ الصَّلَاةَ أَوْ مِثْلَ هَذِهِ الصَّلَاةِ مَعَ رَسُولِ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ قَالَ: وَكَانَ أَبُو بَكْرٍ وَعُمَرُ يَقُومَانِ فِي الصَّفِّ الْمُقَدَّمِ عَنْ يَمِينِهِ وَكَانَ رَجُلٌ قَدْ شَهِدَ التَّكْبِيرَةَ الْأُولَى مِنَ الصَّلَاةِ فَصَلَّى نَبِيُّ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ ثُمَّ سَلَّمَ عَنْ يَمِينِهِ وَعَنْ يَسَارِهِ حَتَّى رَأَيْنَا بَيَاضَ خَدَّيْهِ ثُمَّ انْفَتَلَ كَانْفِتَالِ أَبِي رِمْثَةَ يَعْنِي نَفْسَهُ فَقَامَ الرَّجُلُ الَّذِي أَدْرَكَ مَعَهُ التَّكْبِيرَةَ الْأُولَى مِنَ الصَّلَاةِ يَشْفَعُ فَوَثَبَ إِلَيْهِ عُمَرُ فَأَخَذَ بمنكبه فَهَزَّهُ ثُمَّ قَالَ اجْلِسْ فَإِنَّهُ لَمْ يُهْلِكْ أَهْلَ الْكِتَابِ إِلَّا أَنَّهُ لَمْ يَكُنْ بَيْنَ صلواتهم فَصْلٌ. فَرَفَعَ النَّبِيُّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ بَصَره فَقَالَ: «أصَاب الله بك يَا ابْن الْخطاب» . رَوَاهُ أَبُو دَاوُد