وَيَقُولُونَ مَتَىٰ هَـٰذَا ٱلْوَعْدُ إِن كُنتُمْ صَـٰدِقِينَ
Wayaqooloona mat a h atha alwaAAdu in kuntum sa diqeen a and so they ask, "When is this promise [of resurrection and judgment] to be fulfilled? [Answer this, O you who believe in it,] if you are men of truth!"36
 - Mohammad Asad
They ask you: "When will this promise of resurrection be fulfilled, if you are telling the truth?"
 - Muhammad Farooq-i-Azam Malik
And they ask 'the believers', 'When will this threat come to pass, if what you say is true?'
 - Mustafa Khattab
And they say: When is this promise (to be fulfilled) if ye are truthful?
 - Marmaduke Pickthall
They say: "When will this promise (come to pass) if ye are telling the truth?"
 - Abdullah Yusuf Ali