Musannaf Ibn Abi Shaybah

Hazrat Abu Alaa narrates that Hazrat Abu Musa had made a will regarding the digging of the grave that the grave should be dug deep.

It is also narrated in a similar manner from Hazrat Zahhak bin Abdur Rahman.

Hasan and Muhammad preferred that the grave be deep.

It is narrated from Hazrat Hisham that Hasan and Muhammad used to say that the grave should be dug deep.

Ibrahim says that the grave should be dug up to the navel.

Hasan narrates that Hazrat Umar had instructed that the grave should be dug deep in both length and width.