In the seventh verse (49), after citing a particular excuse made by a noted hypocrite called Jadd ibn Qays, a comment has been made which shows how astray he had gone. The excuse for not going on Jihad he came up with was that he happened to be a young man. If he went out against the Roman Christians in their territory, there were chances that he might fall into the snare of their beautiful women! (` Do not expose me to an ordeal' ) The Qur'an responded by saying: أَلَا فِي الْفِتْنَةِ سَقَطُوا (Look! they have already fallen into an ordeal). It means that such people were not very smart. They were trying to hide behind the excuse of an imaginary ordeal, not realizing that they had already fallen into the sin of a certain ordeal, the ordeal of acting against the command of Allah and His Messenger, and of deserting the Jihad effort, right on the spot.
The last sentence of the verse: وَإِنَّ جَهَنَّمَ لَمُحِيطَةٌ بِالْكَافِرِينَ (and certainly the Jahannam has the disbelievers encircled) could have two meanings. It could either mean that the Hell would encircle them in the Hereafter. Or, it could mean that the very chain of causes, which are operating to take them to Hell, and which have them all encircled at that time, are what has been equated with Hell. Given this interpretation, it would suggest that they happen to be, even now, within the larger circle of nothing but Hell.