Tafsir of Ad-Dhariyat 51:12

(They ask)—that is, by way of haste and mockery—(when is the Day of Recompense?)

The phrase is an object of "they ask," functioning in the same manner as "they say," due to the meaning of speech contained within it, or because of an implied "saying"—that is: "They say, 'When will the occurrence of the Day of Recompense be?'" The occurrence is implied so that the question pertains to the event itself, as is the known usage of ayyan (when).

There is no difficulty in making time "temporal," for when "the Day" is treated as promised and awaited, as in His, the Exalted’s, saying: "So watch for the Day when the sky will bring...", it becomes appended to things that are temporal. Likewise, every day that has an exemplar, such as the Day of Eid or Nayruz, follows this pattern. This is common in the customs of both the Arabs and the non-Arabs. Furthermore, it is permissible according to the Ash'arites for time to have a time, as detailed in its proper place. It has been recited as iyyan with a kasra on the hamza, which is a recognized dialect.