Narrated Abu Huraira (Radi-Allahu 'anhu):

that Allah's Apostle (Sallallahu 'Alaihi Wa Sallam) said, "Whoever attends
the funeral procession till he offers the funeral prayer for it, will get a
reward equal to one Qirat, and whoever accompanies it till burial, will get
a reward equal to two Qirats." It was asked, "What are two Qirats?" He
replied, "Like two huge mountains."

Bukhari Vol. 2 : No. 410

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