Khaibar: a reward for those at Hudaibiyah

سَيَقُولُ ٱلْمُخَلَّفُونَ إِذَا ٱنطَلَقْتُمْ إِلَىٰ مَغَانِمَ لِتَأْخُذُوهَا ذَرُونَا نَتَّبِعْكُمْ ۖ يُرِيدُونَ أَن يُبَدِّلُوا۟ كَلَٰمَ ٱللَّهِ ۚ قُل لَّن تَتَّبِعُونَا كَذَٰلِكُمْ قَالَ ٱللَّهُ مِن قَبْلُ ۖ فَسَيَقُولُونَ بَلْ تَحْسُدُونَنَا ۚ بَلْ كَانُوا۟ لَا يَفْقَهُونَ إِلَّا قَلِيلًۭا

Those who lagged behind (will say), when ye (are free to) march and take booty (in war): "Permit us to follow you." They wish to change Allah's decree: Say: "Not thus will ye follow us: Allah has already declared (this) beforehand": then they will say, "But ye are jealous of us." Nay, but little do they understand (such things).