Surah Yunus 10:48

وَيَقُولُونَ مَتَىٰ هَـٰذَا ٱلْوَعْدُ إِن كُنتُمْ صَـٰدِقِينَ

And they say, "When is [the fulfillment of] this promise, if you should be truthful?"

Translation: Saheeh International

Tafsir

And they say ‘When will this promise of chastisement come to pass if you are truthful about it?’

Excerpt from Tafsir al-Jalalayn, commentary on 10:48, via Quran.com. The reader has the full commentary and 9 more tafsirs.