It is narrated from Hazrat Abu Huraira (may Allah be pleased with him) that the Holy Prophet (peace and blessings be upon him) said: Whoever offers the funeral prayer for someone will receive a reward equal to one qirat, and whoever waits until the burial is completed will receive a reward equal to two qirats. The narrator says: I asked Hazrat Abu Huraira (may Allah be pleased with him), "What is meant by qirat?" He replied: "It is equal to the mountain of Uhud."
Hadith Referenceمسند احمد / مسند المكثرين من الصحابة / 10142