قبر کے متعلق ہدایت

Jabir (RA) reported that the Messenger of Allah ﷺ forbade making a grave solid (plastering or cementing it), building a structure over it, and sitting upon it. (Muslim)

The grave is the first stage of the journey to the Hereafter — for the believer a garden from the gardens of Paradise, and for the disbeliever a pit from the pits of Hell. The Prophet ﷺ gave very clear directions concerning the grave, and the above hadith contains several of them:
One direction is that a grave should be kept so plain in appearance that seeing it awakens a sense of the impermanence and mortality of this world and stirs the remembrance of, and concern for, the Hereafter. This is why plastering it and raising a structure over it were forbidden. One narration relates that the Prophet ﷺ appointed Sayyiduna 'Ali (RA) to the task, telling him: do not leave any image you see, but efface it; and any grave you find raised high, level it (Muslim). "Efface" here means: lower it so much that it comes close to the level of the ground and only its mark remains. Another narration tells us that the blessed grave of the Prophet ﷺ was like the hump of a camel (Bukhari); accordingly it is recommended to keep a grave raised about a hand-span.
The second direction is that sitting on a grave is forbidden. Sitting on a grave was prohibited because it is against the honour and dignity of the believer, in that climbing upon and sitting on a grave amounts to disrespect and belittlement of its occupant.
Another noble hadith comes in these words: "Do not sit on graves, nor pray facing towards them" (Muslim). A particular aim behind forbidding prayer facing a grave is also to protect the Ummah from any suspicion of shirk.