The door as a motif in funerary art symbolizes mystery. The door is the pathway from the earthly realm to the next. In this example, the mystery seems to be lifted—here the mourning figure appears to leading the way to the next realm with her oil lamp.
The Bible verse, II Samuel: Chapter 22, verse 29, says, “For thou art my lamp, O LORD: and the LORD will lighten my darkness.”
The light emanating from the lamp represents the pathway to Truth and to Knowledge.