Tafsir of Az-Zumar 39:34

"For them is what they wish for with their Lord." This is an explanation of the excellent return in the Hereafter for those described as coming with the truth and believing in it, following the explanation of the excellent deeds they performed in this world. That is, they shall have everything they wish for in terms of acquiring benefits and warding off harms in the Hereafter—not only in Paradise, for some of what they wish for, such as the expiation of sins and safety from the Greatest Terror and the rest of the horrors of the Day of Resurrection, occurs before entering Paradise.

"That"—meaning that which has been mentioned regarding the attainment of all that they wish for—"is the reward of the doers of good."

That is, those who perfected their deeds. The intended meaning of this phrase refers to those previously spoken of, but the apparent noun has been used in place of the pronoun to draw attention to the cause for obtaining this reward. It is also said that the meaning is general, encompassing them and others, with them being the primary recipients.