BUKHARI 943:
from Ibn ʿUmar Naḥw from Qawl Mujāhid Idhā Ākhtalaṭūā Qiyām And Zād Ibn ʿUmar —
Ibn ʿUmar said something similar to Mujahid's saying: Whenever (Muslims and non-Muslims) stand face to face in battle, the Muslims can pray while standing. Ibn ʿUmar added, "The Prophet ﷺ said, 'If the number of the enemy is greater than the Muslims, they can pray while standing or riding (individually).' "
البخاري ٩٤٣:
عن ابن عمر نحو عن قول مجاهد اذا اختلطوا قيام و زاد ابن عمر —
عَنِ النَّبِيِّ ﷺ وَإِنْ كَانُوا أَكْثَرَ مِنْ ذَلِكَ فَلْيُصَلُّوا قِيَامًا وَرُكْبَانًا
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