It has been narrated on the authority of Ibn Amir who said:

I heard the Messenger of Allah (ﷺ) say-and he was delivering a sermon from the pulpit: Prepare to meet them with as much strength as you can afford. Beware, strength consists in archery. Beware, strength consists in archery. Beware, strength consists in archery.

حَدَّثَنَا هَارُونُ بْنُ مَعْرُوفٍ، أَخْبَرَنَا ابْنُ وَهْبٍ، أَخْبَرَنِي عَمْرُو بْنُ الْحَارِثِ، عَنْ أَبِي عَلِيٍّ، ثُمَامَةَ بْنِ شُفَىٍّ أَنَّهُ سَمِعَ عُقْبَةَ بْنَ عَامِرٍ، يَقُولُ سَمِعْتُ رَسُولَ اللَّهِ صلى الله عليه وسلم وَهُوَ عَلَى الْمِنْبَرِ يَقُولُ ‏

‏ وَأَعِدُّوا لَهُمْ مَا اسْتَطَعْتُمْ مِنْ قُوَّةٍ أَلاَ إِنَّ الْقُوَّةَ الرَّمْىُ أَلاَ إِنَّ الْقُوَّةَ الرَّمْىُ أَلاَ إِنَّ الْقُوَّةَ الرَّمْىُ ‏

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