We set out with the Messenger of Allah ﷺ in the year of Khaybar. When we reached al-Sahba, the Messenger of Allah led us in the afternoon prayer. After praying, he called for food, but nothing was brought except parched barley. We ate and drank, then the Prophet ﷺ rose for the sunset prayer, rinsed his mouth, and prayed Maghrib without performing ablution.
خرجنا مع رسول الله ﷺ عام خيبر حتى إذا كنا بالصهباء صلى لنا رسول الله العصر، فلما صلى دعا بالأطعمة، فلم يؤت إلا بالسويق، فأكلنا وشربنا، ثم قام النبي ﷺ إلى لمغرب، فمضمض، ثم صلى المغرب ولم يتوضأ.
Bukhari related it in the chapter on wudu (215), from the hadith of Yahya bin Saeed, who said, Bashir bin Yasar informed me, who said, Suwayd bin Numan narrated to me... and he related the hadith. The hadith is also mentioned in the chapter on not performing wudu after eating something touched by fire.