Abu Dawud Book 2, Hadith Number 1526.
Chapter : On seeking pardon and repentance.
Narated By Aws b. Aws : The Apostle of Allah (PBUH) said: Among the most excellent of your days is Friday; so invoke many blessings on me that day, for your blessing will be submitted to me. They (the Companions) asked: Apostle of Allah, how can our blessing be submitted to you, when your body is decayed? He said: Allah has prohibited the earth from consuming the bodies of the Prophets.