It is narrated from Sayyiduna Ibn Umar (may Allah be pleased with them both) that the Messenger of Allah (peace and blessings be upon him) said: "Whoever accompanies a funeral and offers the funeral prayer will receive a reward equal to one qirat." Someone asked the Noble Prophet (peace and blessings be upon him), "What is a qirat?" The Noble Prophet (peace and blessings be upon him) replied: "It is equal to the mountain of Uhud."
Hadith Referenceمسند احمد / مسند المكثرين من الصحابة / 4867