فَإِنْ خِفْتُمْ فَرِجَالًا أَوْ رُكْبَانًا ۖ فَإِذَا أَمِنْتُمْ فَاذْكُرُوا اللَّهَ كَمَا عَلَّمَكُمْ مَا لَمْ تَكُونُوا تَعْلَمُونَ

Surah Al-Baqarah : 239
And if you fear [an enemy, then pray] on foot or riding. But when you are secure, then remember Allah [in prayer], as He has taught you that which you did not [previously] know.

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