Sahih Bukhari Volume 5, Book 64, Hadith 4197

حَدَّثَنَا عَبْدُ اللَّهِ بْنُ مَسْلَمَةَ، عَنْ مَالِكٍ، عَنْ يَحْيَى بْنِ سَعِيدٍ، عَنْ بُشَيْرِ بْنِ يَسَارٍ، أَنَّ سُوَيْدَ بْنَ النُّعْمَانِ، أَخْبَرَهُ أَنَّهُ، خَرَجَ مَعَ النَّبِيِّ صلى الله عليه وسلم عَامَ خَيْبَرَ، حَتَّى إِذَا كُنَّا بِالصَّهْبَاءِ ـ وَهْىَ مِنْ أَدْنَى خَيْبَرَ ـ صَلَّى الْعَصْرَ، ثُمَّ دَعَا بِالأَزْوَادِ فَلَمْ يُؤْتَ إِلاَّ بِالسَّوِيقِ، فَأَمَرَ بِهِ فَثُرِّيَ، فَأَكَلَ وَأَكَلْنَا، ثُمَّ قَامَ إِلَى الْمَغْرِبِ، فَمَضْمَضَ وَمَضْمَضْنَا، ثُمَّ صَلَّى وَلَمْ يَتَوَضَّأْ

Narrated By Suwaid bin An-Numan : I went out in the company of the Prophet in the year of Khaibar, and when we reached As Sahba' which is the lower part of Khaibar, the Prophet offered the Asr prayer and then asked the people to collect the journey food. Nothing was brought but Sawiq which the Prophet ordered to be moistened with water, and then he ate it and we also ate it. Then he got up to offer the Maghrib prayer. He washed his mouth, and we too washed our mouths, and then he offered the prayer without repeating his abulution.