Sahih al-Bukhari, Volume 9, Book 88, Hadith 246 (USC-MSA) ⓘ
Narrated Abu Sa`id: One day Allah's Messenger narrated to us a long narration about Ad-Dajjal and among the things he narrated to us, was: "Ad-Dajjal will come, and he will be forbidden to enter the mountain passes of Medina. He will encamp in one of the salt areas neighboring Medina and there will appear to him a man who will be the best or one of the best of the people. He will say 'I testify that you are Ad-Dajjal whose story Allah's Messenger has told us.' Ad-Dajjal will say (to his audience), 'Look, if I kill this man and then give him life, will you have any doubt about my claim?' They will reply, 'No,' Then Ad- Dajjal will kill that man and then will make him alive. The man will say, 'By Allah, now I recognize you more than ever!' Ad-Dajjal will then try to kill him (again) but he will not be given the power to do so."
حَدَّثَنَا أَبُو الْيَمَانِ، أَخْبَرَنَا شُعَيْبٌ، عَنِ الزُّهْرِيِّ، أَخْبَرَنِي عُبَيْدُ اللَّهِ بْنُ عَبْدِ اللَّهِ بْنِ عُتْبَةَ بْنِ مَسْعُودٍ، أَنَّ أَبَا سَعِيدٍ، قَالَ حَدَّثَنَا رَسُولُ اللَّهِ صلى الله عليه وسلم يَوْمًا حَدِيثًا طَوِيلاً عَنِ الدَّجَّالِ، فَكَانَ فِيمَا يُحَدِّثُنَا بِهِ أَنَّهُ قَالَ " يَأْتِي الدَّجَّالُ وَهُوَ مُحَرَّمٌ عَلَيْهِ أَنْ يَدْخُلَ نِقَابَ الْمَدِينَةِ، فَيَنْزِلُ بَعْضَ السِّبَاخِ الَّتِي تَلِي الْمَدِينَةَ، فَيَخْرُجُ إِلَيْهِ يَوْمَئِذٍ رَجُلٌ وَهْوَ خَيْرُ النَّاسِ أَوْ مِنْ خِيَارِ النَّاسِ، فَيَقُولُ أَشْهَدُ أَنَّكَ الدَّجَّالُ الَّذِي حَدَّثَنَا رَسُولُ اللَّهِ صلى الله عليه وسلم حَدِيثَهُ، فَيَقُولُ الدَّجَّالُ أَرَأَيْتُمْ إِنْ قَتَلْتُ هَذَا ثُمَّ أَحْيَيْتُهُ، هَلْ تَشُكُّونَ فِي الأَمْرِ فَيَقُولُونَ لاَ. فَيَقْتُلُهُ ثُمَّ يُحْيِيهِ فَيَقُولُ وَاللَّهِ مَا كُنْتُ فِيكَ أَشَدَّ بَصِيرَةً مِنِّي الْيَوْمَ. فَيُرِيدُ الدَّجَّالُ أَنْ يَقْتُلَهُ فَلاَ يُسَلَّطُ عَلَيْهِ " .
also referenced under: Book 92, Hadith 79 (In-Book) & Hadith 7132 (DarusSalam)