Messenger of Allah ﷺ told us a long narrative about Ad-Dajjal, and among the many things he mentioned, was his saying, "Ad-Dajjal will come and it will be forbidden for him to pass through the entrances of Medina. He will land in some of the salty barren areas (outside) Medina; on that day the best man or one of the best men will come up to him and say, 'I testify that you are the same Dajjal whose description was given to us by Messenger of Allah ﷺ .' Ad-Dajjal will say to the people, 'If I kill this man and bring him back to life again, will you doubt my claim?' They will say, 'No.' Then Ad-Dajjal will kill that man and bring him back to life. That man will say, 'Now I know your reality better than before.' Ad-Dajjal will say, 'I want to kill him but I cannot.' "  

أَنَّ أَبَا سَعِيدٍ الْخُدْرِيَّ ؓ قَالَ حَدَّثَنَا رَسُولُ اللَّهِ ﷺ حَدِيثًا طَوِيلاً عَنِ الدَّجَّالِ فَكَانَ فِيمَا حَدَّثَنَا بِهِ أَنْ قَالَ يَأْتِي الدَّجَّالُ وَهُوَ مُحَرَّمٌ عَلَيْهِ أَنْ يَدْخُلَ نِقَابَ الْمَدِينَةِ بَعْضَ السِّبَاخِ الَّتِي بِالْمَدِينَةِ فَيَخْرُجُ إِلَيْهِ يَوْمَئِذٍ رَجُلٌ هُوَ خَيْرُ النَّاسِ أَوْ مِنْ خَيْرِ النَّاسِ فَيَقُولُ أَشْهَدُ أَنَّكَ الدَّجَّالُ الَّذِي حَدَّثَنَا عَنْكَ رَسُولُ اللَّهِ ﷺ حَدِيثَهُ فَيَقُولُ الدَّجَّالُ أَرَأَيْتَ إِنْ قَتَلْتُ هَذَا ثُمَّ أَحْيَيْتُهُ هَلْ تَشُكُّونَ فِي الأَمْرِ فَيَقُولُونَ لاَ فَيَقْتُلُهُ ثُمَّ يُحْيِيهِ فَيَقُولُ حِينَ يُحْيِيهِ وَاللَّهِ مَا كُنْتُ قَطُّ أَشَدَّ بَصِيرَةً مِنِّي الْيَوْمَ فَيَقُولُ الدَّجَّالُ أَقْتُلُهُ فَلاَ أُسَلَّطُ عَلَيْهِ