This concept explores the allegory presented in Section 3 of Attar's Mosibat Nameh, where the wise fool Bahlool is found sleeping on a grave. When asked why he sleeps there, Bahlool claims he is listening to the dead person swearing a secret oath: that the earth will eventually draw every living person into the grave to 'sleep in blood' just like the deceased. This tale serves as a stark memento mori, using Bahlool's feigned madness to convey the absolute inevitability of death and the shared mortal fate of all humanity.