Al-Aswad bin Qays relates: I heard Sayyiduna Jundub (may Allah be pleased with him) say: The Prophet (peace and blessings be upon him) was walking when suddenly a stone struck him and he (peace and blessings be upon him) stumbled, and his (peace and blessings be upon him) finger 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 / 1690