﴿ فَأَعْرِضْ عَنْهُمْ وَٱنتَظِرْ إِنَّهُم مُّنتَظِرُونَ ﴾

“and then leave them alone, and wait [for the truth to unfold as] they, behold, are waiting.”

So turn away from them and wait for the chastisement to be sent down on them. They too are waiting for your death to take place or for you to be killed and so be rid of you — this was revealed before the command to fight them.