Grave
The womb of the earth and of the Earth Mother; the body imprisoning the soul. A symbol of the Mother Goddess as both death-dealing and sheltering; dying to the world. In Alchemy the grave, with the skull and the raven, represent the blackening and mortification of the first stage of the Lesser Work, it is 'earth to earth'. From: An Illustrated Encyclopaedia of Traditional Symbols (J.C. Cooper)
On a very physical level graves do not appear to be very happy omens. However, graves could also have deeper and more spiritual meaning. They could represent things which require deep thinking and are not "on the surface". Graves could also symbolize the unconscious. From On Line Dictionary
Songs referenced:
Father Lucifer