Yunus 48

وَيَقُولُونَ مَتَىٰ هَٰذَا ٱلْوَعْدُ إِن كُنتُمْ صَٰدِقِينَ ﴿٤٨﴾

Wayaqooloona mata hatha alwaAAdu in kuntum sadiqeena

And they say: "When will be this promise (the torment or the Day of Resurrection), - if you speak the truth?" The Noble Quran