﴿ فَإِمَّا تَثْقَفَنَّهُمْ فِى ٱلْحَرْبِ فَشَرِّدْ بِهِم مَّنْ خَلْفَهُمْ لَعَلَّهُمْ يَذَّكَّرُونَ ﴾

“if thou find them at war [with you], make of them a fearsome example for those who follow them, so that they might take it to heart;”

(If thou comest on them) if you imprison them (in the war, deal with them so as to strike fear in those who are behind them) such that they serve as a lesson to those who are behind them, (that haply they may remember) i.e. take admonition and avoid breaking their treaties.