IBNHIBBAN 2258:
from Ibn ʿUmar —
[Machine] The Prophet ﷺ entered the mosque of Bani Amr ibn Auf, which is known as the Quba Mosque. Some men from the Ansar (helpers) greeted him. Ibn Umar said, "So I asked Suhaib, who was with him, how the Prophet ﷺ used to respond when someone greeted him while he was praying?" He said, "He used to gesture with his hand."
ابن حبّان ٢٢٥٨:
عن ابن عمر —
دَخَلَ النَّبِيُّ ﷺ مَسْجِدَ بَنِي عَمْرِو بْنِ عَوْفٍ يَعْنِي مَسْجِدَ قُبَاءٍ فَدَخَلَ رِجَالٌ مِنَ الْأَنْصَارِ يُسَلِّمُونَ عَلَيْهِ قَالَ ابْنُ عُمَرَ فَسَأَلْتُ صُهَيْبًا وَكَانَ مَعَهُ كَيْفَ كَانَ النَّبِيُّ ﷺ يَفْعَلُ إِذَا كَانَ يُسَلَّمُ عَلَيْهِ وَهُوَ يُصَلِّي؟ فَقَالَ «كَانَ يُشِيرُ بِيَدِهِ»
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