What is the required manner of dealing with the earth after finishing the grave excavation (lahd)?

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After completing the side cavity (lahd), the earth must be poured over it. The grave must be raised above the ground by the height of one span so that it may be identified as a grave, thus prompting respect and supplication for its occupant. This practice is supported by the narration from Al-Saji, reporting from Jabir, that the Prophet, peace be upon him, raised his grave by the height of one span. Furthermore, when Al-Qasim ibn Muhammad asked Umm Salamah to show him the grave of the Messenger of Allah and his two companions, she revealed three graves that were neither raised high nor level with the ground, but were flattened with the red gravel of the courtyard (reported by Abu Dawud).