What is the ruling on burying a deceased person in the grave of another deceased person? And is it permissible to set a limit of forty years?

The questioner : You said, our Shaykh... you said that it is not permissible to open a person's grave and bury someone on top of it except after forty years?

The Shaykh : No, I do not say forty; what is this talk? I do not say forty, nor do I say twenty, nor do I say one hundred; this varies from land to land until it is exhausted.

The questioner : The bones do not...

The Shaykh : How?

The questioner : Until the bones are exhausted?

The Shaykh : Yes, the bones are exhausted... they become dust.

The questioner : All the bones become...

Another questioner : My master, regarding the graves...
...

The Shaykh : Is it permissible, what?

Another questioner : Is it permissible?

The Shaykh : No, it is not permissible.

Another questioner : Above the ground, you mean?
...

The Shaykh : Just... above the ground.
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Another questioner : Not under the ground.

Another questioner : ... for the family...

Another questioner : They made them into levels, our Shaykh.

The Shaykh : Levels as well?! Allah is sufficient for us, and He is the best Disposer of affairs.

Another questioner : I mean the first level is in the ground, the second level is on the surface of the ground, and the third level is even higher.
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