It is narrated from Hazrat Amr bin Abasah (may Allah be pleased with him) that the Holy Prophet (peace and blessings of Allah be upon him) said: Whoever strives in the way of Allah even to the extent of the amount of milk that descends into the udder of a she-camel, Allah makes the fire of Hell forbidden upon his face.
Hadith Referenceمسند احمد / تتمہ مُسْنَدِ الْكُوفِيِّينَ / 19444
Hadith Gradingحکم دارالسلام:حديث قوي لغيره، وهذا إسناد ضعيف، عبدالعزيز بن عبيد الله ضعيف