قرآن ﴿ ولا يحسبن الذين كفروا سبقوا إنهم لا يعجزون واعدوا لهم ما استطعتم من قوة ومن رباط الخيل ترهبون به عدو الله وعدوكم وآخرين من دونهم لا تعلمونهم الله يعلمهم وما تنفقوا من شيء في سبيل الله يوف اليكم وأنتم لا تظلمون وإن جنحوا للسلم فاجنح لها وتوكل على الله إنه هو السميع العليم ﴾ الأنفال ٥٩-٦١
قرآن ﴿ واعدوا لهم ما استطعتم من قوة ومن رباط الخيل ترهبون به عدو الله وعدوكم وآخرين من دونهم لا تعلمونهم الله يعلمهم وما تنفقوا من شيء في سبيل الله يُوَفَّ اليكم وأنتم لا تظلمون ﴾ لما إتفق في قصة بدر أن قصدوا الكفار بلا تكميل آلة ولا عُدَّة وأمره تعالى بالتشريد وبنبذ العهد للناقضين كان ذلك سبباً للأخذ في قتاله والتمالؤ عليه فأمره تعالى للمؤمنين بإعداد ما قدروا عليه من القوة للجهاد والإعداد الأرصاد وعلّق ذلك بالإستطاعة لطفاً منه تعالى والمخاطبون هم المؤمنين والضمير في ﴿ لهم ﴾ عائد على الكفار المتقدّمي الذكر وهم المأمور بحربهم في ذلك الوقت ويعمّ من بعده
البحر المحيط لابي حيان
{ Let not those who have disbelieved reckon that they have gotten away; indeed they can not frustrate. Prepare for them whatever you are able of force and tethers of steeds, so that you can terrify Allah’s enemy and your enemy with it, as well as others besides them that you do not know but that Allah knows; and anything you spend in the cause of Allah will be paid back to you, and you will not be oppressed. But if they incline to peace, then incline to it; and rely on Allah, indeed He is the one who hears, the one who knows } Al-anfal 59-61
{ Prepare for them whatever you are able of force and tethers of steeds, so that you can terrify Allah’s enemy and your enemy with it, as well as others besides them that you do not know but that Allah knows; and anything you spend in the cause of Allah will be paid back to you, and you will not be oppressed } . When it came to pass in the account of Badr that they had set their sights on the Disbelievers without a complete array of tools or gear, and the Most High ordered them to drive away the violators and disregard the pact with them, this became reason to engage in fighting them and join forces against them. So the Most High ordered the Believers to prepare whatever they could of force for jihad and set aside preparations, and made this conditional to their capability as an act of kindness from Him Most High. Those being addressed are the Believers, and the object pronoun { for them } denotes the Disbelievers [Kuffar] referred to earlier, those against whom war was ordered at that time, although it became universal after this.
Abu Hayyan, Al-bahr Al-muhit [The All-embracing Sea]