Back 
Surah 15. Al-Hijr
Ayah 61 - 66
61فَلَمَّا جَآءَ ءَالَ لُوطٍ ٱلْمُرْسَلُونَ
62قَالَ إِنَّكُمْ قَوْمٌ مُّنكَرُونَ
63قَالُوا۟ بَلْ جِئْنَـٰكَ بِمَا كَانُوا۟ فِيهِ يَمْتَرُونَ
64وَأَتَيْنَـٰكَ بِٱلْحَقِّ وَإِنَّا لَصَـٰدِقُونَ
65فَأَسْرِ بِأَهْلِكَ بِقِطْعٍ مِّنَ ٱلَّيْلِ وَٱتَّبِعْ أَدْبَـٰرَهُمْ وَلَا يَلْتَفِتْ مِنكُمْ أَحَدٌ وَٱمْضُوا۟ حَيْثُ تُؤْمَرُونَ
66وَقَضَيْنَآ إِلَيْهِ ذَٰلِكَ ٱلْأَمْرَ أَنَّ دَابِرَ هَـٰٓؤُلَآءِ مَقْطُوعٌ مُّصْبِحِينَ
[61-66] Afterwards when these envoys came to the house of Lot,35 he said, "You appear to be strangers."36 They answered, "Nay, but we have come to you with that concerning which these people had doubts. We tell you the truth that we have come to you with the truth. You should, therefore, depart with your people in the last hours of the night and you yourself should follow them in their rear;37 let none of you turn round to look behind;38 go straight where you are being bidden." And We informed him of Our decree that they shall be utterly destroyed by the next morning.
35Please compare this with VII: 80-84 and XI: 77-83.
36Here the story has been related in brief. But we learn from XI: 77-83 that Prophet Lot was greatly perturbed and distressed at the visit of the angels. He said to himself, "This is a day of woe." The reason why he was distressed, as implied in the Qur'an and explicitly expressed in the Traditions, was that the angels had come to Prophet Lot in the shape of beautiful boys, and he knew how perverse and wicked his people were. He was distressed for he could not send them away because they were his guests, and because he did not know how to protect them from those villains.
37That is, “You should walk behind your people lest anyone of them should stay behind.”
38It did not mean: "look not behind thee, lest thou be consumed."as stated in the Bible. But it merely meant to warn them: "None of you should turn round to see what was happening behind them lest you should stop to see the fun, when you heard the cries of the smitten people. For it is neither the time of enjoying "fun", nor of shedding tears of regret. If you stop even for a minute in the territory of the smitten people you also might get hurt from the rain of stones."