Sahih al-Bukhari, Hadith 6146 ⓘ
Narrated Jundub: While the Prophet was walking, a stone hit his foot and stumbled and his toe was injured. He then (quoting a poetic verse) said, "You are not more than a toe which has been bathed in blood in Allah's Cause."
حَدَّثَنَا أَبُو نُعَيْمٍ، حَدَّثَنَا سُفْيَانُ، عَنِ الأَسْوَدِ بْنِ قَيْسٍ، سَمِعْتُ جُنْدَبًا، يَقُولُ بَيْنَمَا النَّبِيُّ صلى الله عليه وسلم يَمْشِي إِذْ أَصَابَهُ حَجَرٌ فَعَثَرَ فَدَمِيَتْ إِصْبَعُهُ فَقَالَ " هَلْ أَنْتِ إِلاَّ إِصْبَعٌ دَمِيتِ وَفِي سَبِيلِ اللَّهِ مَا لَقِيتِ " .
also referenced under: Book 78, Hadith 172 (In-Book) & Volume 8, Book 73, Hadith 167 (USC-MSA)