It is narrated from a Companion (may Allah be pleased with him) that the Noble Prophet (peace and blessings be upon him) said: Whoever suffers any harm to his body and leaves it for the sake of Allah, it will become an expiation for him.
Hadith Referenceمسند احمد / مسند الأنصار رضي الله عنهم / 23494
Hadith Gradingحکم دارالسلام:صحيح لغيره، وهذا إسناد ضعيف لضعف مجالد