Djed

The Djed Pillar was a common symbol throughout the New Kingdom, representing medicine and stability. The Djed was actually the backbone of Osiris, king of the Underworld. After osiris was murdered by Set, his backbone was never recovered by Isis, becoming the Banebdjedet, the spirtit of osiris's backbone. Banebdedet had four ram heads, depicting the four dieties of the sun god. The Djed itself reprents the base of a bull's spine in Egyptian Mythology.

Similarities with Khnum
Banebdjedet was the equilivent of the god Khnum in lower egypt. Khnum was one of the earliest gods featured in Egyptian Mythology, and was believed to create the bodies of children out of clay from the banks of the nile river. Although Banebdjedet was not considered to have the same role in mythology as Khnum, who was mainly worshiped in Upper Egypt, he was treated as a similar figure, and may have had a similar role according to the Gordon-Schwabe theroy.

Worship
During the Feast of the Tail, or Sed Festival, a Djed pillar would be raised as a symbol of the potency and duration of the pharaoh's rule. Ptah and Tatenateen were reffered to as the noble Djed.