It is narrated from Jundub (may Allah be pleased with him) that the Prophet (peace and blessings of Allah be upon him) was participating in a battle when blood started to flow from his finger. The Prophet (peace and blessings of Allah be upon him) said: "It is only a finger that has bled, and whatever pain you have suffered is in the way of Allah." Agreed upon.
Hadith Referenceمشكوة المصابيح / كتاب الآداب / 4788
Hadith Gradingالألبانی:مُتَّفق عَلَيْهِ | زبیر علی زئی:متفق عليه
Hadith Takhrij´تحقيق و تخريج: محدث العصر حافظ زبير على زئي رحمه الله` «متفق عليه، رواه البخاري (2802) و مسلم (1796/112)»