Instead, they say (throwing out a challenge): "When will this judgment take place (which will cause everything to appear in all clarity), if you are truthful (in your threats)?"
They say, “When will be the conquest (the absolute conquest [fath] – the complete unveiling of the reality through the experience of death) if you are of the truthful?”
Sayyed Abbas Sadr-Ameli
And they ask: 'When shall be this Victory, if you are truthful?
Al-muntakhab fi tafsir al-Qur'an al-Karim
And they -the infidels- insolently challenge you O Muhammad to overcome them, asking: "On what day do you expect victory to sit on your helm if you are declaring the truth!"