لَوْ يَعْلَمُ ٱلَّذِينَ كَفَرُوا۟ حِينَ لَا يَكُفُّونَ عَن وُجُوهِهِمُ ٱلنَّارَ وَلَا عَن ظُهُورِهِمْ وَلَا هُمْ يُنصَرُونَ
Commentary:
The context shows and the wording of the present verse also lends support to the inference that the allusion in the word "fire" is to "the fire of war." The disbelievers ignited that fire and were themselves consumed in it. They were destroyed by the weapon which they employed against the believers. They drew the sword against Islam and by the sword they perished.
The words, the fire from their faces, signify the punishment that they will see in front of them i.e. the punishment whose signs will be apparent and manifest; and the words "nor from their backs" signify the punishment that will come upon them from behind their backs i.e. the punishment which will overtake them suddenly and unawares. Moreover, the punishment will overwhelm all of them—their leaders who are their faces and the ordinary folk who follow them and blindly accept their lead.
"Fire" here means "the fire of war." The disbelievers ignited that fire and then were themselves consumed in it. They drew the sword against Islam and by the sword they perished. The words, from their faces, signify the punishment they will see in front of them, i.e. its signs will be apparent and manifest; and the words, nor from their backs, signify that the punishment will overtake them suddenly and unawares. Moreover, the punishment will overwhelm all of them—their leaders and the ordinary men (Wujuh also meaning leaders—Lane).