Tafsir of Al-Inshiqaq 84:22

That is, they deny the Quran. This is a transition from the fact that they do not prostrate when it is recited to them, to the fact that they explicitly deny it. Using the relative pronoun (those who) in place of their pronoun (they) serves to record the charge of disbelief against them and to indicate the cause of the judgment. Al-Dahhak and Ibn Abi 'Abla read it as yukathibuna (with a light tha'), with the ya' vocalized with a fatha.