Sahih Muslim 2897
Abu Huraira reported Allah's Messenger (ﷺ) as saying:
The Last Hour would not come until the Romans would land at al-A'maq or in Dabiq. An army consisting of the best (soldiers) of the people of the earth at that time will come from Medina (to counteract them). When they will arrange themselves in ranks, the Romans would say: Do not stand between us and those (Muslims) who took prisoners from amongst us. Let us fight with them; and the Muslims would say: Nay, by Allah, we would never get aside from you and from our brethren that you may fight them. They will then fight and a third (part) of the army would run away, whom Allah will never forgive. A third (part of the army) which would be constituted of excellent martyrs in Allah's eye, would be killed and the third who would never be put to trial would win and they would be conquerors of Constantinople. And as they would be busy in distributing the spoils of war (amongst themselves) after hanging their swords by the olive trees, the Satan would cry: The Dajjal has taken your place among your family. They would then come out, but it would be of no avail. And when they would come to Syria, he would come out while they would be still preparing themselves for battle drawing up the ranks. Certainly, the time of prayer shall come and then Jesus (peace be upon him) son of Mary would descend and would lead them. When the enemy of Allah would see him, it would (disappear) just as the salt dissolves itself in water and if he (Jesus) were not to confront them at all, even then it would dissolve completely, but Allah would kill them by his hand and he would show them their blood on his lance (the lance of Jesus Christ).
حَدَّثَنِي زُهَيْرُ بْنُ حَرْبٍ، حَدَّثَنَا مُعَلَّى بْنُ مَنْصُورٍ، حَدَّثَنَا سُلَيْمَانُ بْنُ بِلاَلٍ، حَدَّثَنَا 
 سُهَيْلٌ، عَنْ أَبِيهِ، عَنْ أَبِي هُرَيْرَةَ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ ‏
"‏ لاَ تَقُومُ السَّاعَةُ
 حَتَّى يَنْزِلَ الرُّومُ بِالأَعْمَاقِ أَوْ بِدَابِقَ فَيَخْرُجُ إِلَيْهِمْ جَيْشٌ مِنَ الْمَدِينَةِ مِنْ خِيَارِ أَهْلِ الأَرْضِ
 يَوْمَئِذٍ فَإِذَا تَصَافُّوا قَالَتِ الرُّومُ خَلُّوا بَيْنَنَا وَبَيْنَ الَّذِينَ سَبَوْا مِنَّا نُقَاتِلْهُمْ ‏.‏ فَيَقُولُ الْمُسْلِمُونَ
 لاَ وَاللَّهِ لاَ نُخَلِّي بَيْنَكُمْ وَبَيْنَ إِخْوَانِنَا ‏.‏ فَيُقَاتِلُونَهُمْ فَيَنْهَزِمُ ثُلُثٌ لاَ يَتُوبُ اللَّهُ عَلَيْهِمْ أَبَدًا
 وَيُقْتَلُ ثُلُثُهُمْ أَفْضَلُ الشُّهَدَاءِ عِنْدَ اللَّهِ وَيَفْتَتِحُ الثُّلُثُ لاَ يُفْتَنُونَ أَبَدًا فَيَفْتَتِحُونَ قُسْطُنْطِينِيَّةَ
 فَبَيْنَمَا هُمْ يَقْتَسِمُونَ الْغَنَائِمَ قَدْ عَلَّقُوا سُيُوفَهُمْ بِالزَّيْتُونِ إِذْ صَاحَ فِيهِمُ الشَّيْطَانُ إِنَّ الْمَسِيحَ
 قَدْ خَلَفَكُمْ فِي أَهْلِيكُمْ ‏.‏ فَيَخْرُجُونَ وَذَلِكَ بَاطِلٌ فَإِذَا جَاءُوا الشَّأْمَ خَرَجَ فَبَيْنَمَا هُمْ يُعِدُّونَ
 لِلْقِتَالِ يُسَوُّونَ الصُّفُوفَ إِذْ أُقِيمَتِ الصَّلاَةُ فَيَنْزِلُ عِيسَى ابْنُ مَرْيَمَ فَأَمَّهُمْ فَإِذَا رَآهُ عَدُوُّ
 اللَّهِ ذَابَ كَمَا يَذُوبُ الْمِلْحُ فِي الْمَاءِ فَلَوْ تَرَكَهُ لاَنْذَابَ حَتَّى يَهْلِكَ وَلَكِنْ يَقْتُلُهُ اللَّهُ بِيَدِهِ فَيُرِيهِمْ
 دَمَهُ فِي حَرْبَتِهِ ‏"‏ ‏.‏