Allah tells us that after Ibrahim had calmed down from the excitement of this good news, he started to ask them why they had come to him. They said,

[إِنَّآ أُرْسِلْنَآ إِلَى قَوْمٍ مُّجْرِمِينَ]

(We have been sent to a guilty people.) meaning the people of Lut. They told him that they were going to save the family of Lut from among those people, except for his wife, because she was one of those who were doomed. Thus it was said,

[إِلاَّ امْرَأَتَهُ قَدَّرْنَآ إِنَّهَا لَمِنَ الْغَـبِرِينَ ]

(Except for his wife, of whom We have decreed that she shall be of those who remain behind.) i.e., she was one of those who would be left behind and will be destroyed.

[فَلَمَّا جَآءَ ءَالَ لُوطٍ الْمُرْسَلُونَ - قَالَ إِنَّكُمْ قَوْمٌ مُّنكَرُونَ - قَالُواْ بَلْ جِئْنَـكَ بِمَا كَانُواْ فِيهِ يَمْتَرُونَ - وَآتَيْنَـكَ بِالْحَقِّ وَإِنَّا لَصَـدِقُونَ ]

(61. Then when the messengers (the angels) came to the family of Lut) (62. He (Lut) said: "Verily, you are people unknown to me.'') (63. They said: "Nay, we have come to you with that (torment) which they have been doubting.'') (64. "And we have brought you the truth and certainly we tell the truth.'')