﴿Upon the disbelievers﴾ means those who used to take the warning lightly and turn away from it because they are firmly established in disbelief, which is the concealment of what must be manifested from the signs of monotheism. And since hardship may be applied to something in which there is ease from some aspects or it may be dealt with and then return to being easy, it has been clarified that it is not like that by His saying: ﴿Not easy﴾. He combined in it between affirming the thing and denying its opposite, confirming its matter and repelling metaphorical interpretations about it, and supporting its existence. And because it is not cut off in any way, its specification with the disbelievers indicates its ease for the believers.