Sahih Muslim , Book 19, Hadith 4437 (USC-MSA) ⓘ

It has been narrated on the authority of Anas that the Messenger of Allah raided Khaibar. One morning we offered prayers in the darkness of early dawn (near Khaibar). Then the Messenger of Allah mounted (his horse). Abu Talha mounted his and I mounted behind Abu Talha on the same horse. The Prophet of Allah rode through the streets of Khaibar and (I rode so close to him) that my knee touched the thigh of the Prophet of Allah. The wrapper got aside from his thigh, and I could see its whiteness. When he entered the town, he said: God is Great. Khaibar shall face destruction. When we descend in the city-square of a people, it is a bad day for them who have been warned (and have not taken heed). He said these words thrice. The people of the town had just come out from (their houses) to go about their jobs. They said (in surprise): Muhammad has come. We captured Khaibar by force.

وَحَدَّثَنِي زُهَيْرُ بْنُ حَرْبٍ، حَدَّثَنَا إِسْمَاعِيلُ، - يَعْنِي ابْنَ عُلَيَّةَ - عَنْ عَبْدِ الْعَزِيزِ، بْنِ صُهَيْبٍ عَنْ أَنَسٍ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم غَزَا خَيْبَرَ قَالَ فَصَلَّيْنَا عِنْدَهَا صَلاَةَ الْغَدَاةِ بِغَلَسٍ فَرَكِبَ نَبِيُّ اللَّهِ صلى الله عليه وسلم وَرَكِبَ أَبُو طَلْحَةَ وَأَنَا رَدِيفُ أَبِي طَلْحَةَ فَأَجْرَى نَبِيُّ اللَّهِ صلى الله عليه وسلم فِي زُقَاقِ خَيْبَرَ وَإِنَّ رُكْبَتِي لَتَمَسُّ فَخِذَ نَبِيِّ اللَّهِ صلى الله عليه وسلم وَانْحَسَرَ الإِزَارُ عَنْ فَخِذِ نَبِيِّ اللَّهِ صلى الله عليه وسلم وَإِنِّي لأَرَى بَيَاضَ فَخِذِ نَبِيِّ اللَّهِ صلى الله عليه وسلم فَلَمَّا دَخَلَ الْقَرْيَةَ قَالَ ‏ "‏ اللَّهُ أَكْبَرُ خَرِبَتْ خَيْبَرُ إِنَّا إِذَا نَزَلْنَا بِسَاحَةِ قَوْمٍ فَسَاءَ صَبَاحُ الْمُنْذَرِينَ ‏" ‏ ‏.‏ قَالَهَا ثَلاَثَ مِرَارٍ قَالَ وَقَدْ خَرَجَ الْقَوْمُ إِلَى أَعْمَالِهِمْ فَقَالُوا مُحَمَّدٌ - قَالَ عَبْدُ الْعَزِيزِ وَقَالَ بَعْضُ أَصْحَابِنَا - وَالْخَمِيسَ قَالَ وَأَصَبْنَاهَا عَنْوَةً ‏.‏