Al-Aswad bin Qays relates that it is narrated from Sayyiduna Jundub bin Sufyan (may Allah be pleased with him): The Prophet (peace and blessings be upon him) was walking when suddenly a stone struck his (peace and blessings be upon him) finger, and it was wounded and bled. So he (peace and blessings be upon him) said: "You are but a finger that has bled, and in the way of Allah is whatever has befallen you."
Hadith Referenceالمعجم الكبير للطبراني / باب الجيم / 1691