BAYHAQI 2288:
from Anas b. Mālik —
[Machine] That the Messenger of Allah ﷺ after the prayer was established, before making the Takbeer, turned his face towards his companions and said, "Straighten your rows and stand close together, for I see you from behind my back. Indeed, I have seen a man touching his shoulder to his brother's shoulder when standing in prayer."
البيهقي ٢٢٨٨:
عن انس بن مالك —
أَنَّ رَسُولَ اللهِ ﷺ بَعْدَ أَنْ أُقِيمَتِ الصَّلَاةُ قَبْلَ أَنْ يُكَبِّرَ أَقْبَلَ بِوَجْهِهِ عَلَى أَصْحَابِهِ فَقَالَ أَقِيمُوا صُفُوفَكُمْ وَتَرَاصُّوا فَإِنِّي أَرَاكُمْ مِنْ وَرَاءِ ظَهْرِي فَلَقَدْ رَأَيْتُ الرَّجُلَ يُلْزِقُ مَنْكِبَهُ بِمَنْكِبِ أَخِيهِ إِذَا قَامَ فِي الصَّلَاةِ
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