The Luz Boneעצם לוז

The indestructible almond-bone of the spine (Bereshit Rabbah 28:3; Zohar II 28b) — the one part of the body that does not decay, nourished only by the Saturday-night melaveh malkah meal, from which the whole body is rebuilt at the resurrection, watered by the dew of light (tal). Luz is also the city renamed Beth-El — "the house of God" — the place of Jacob's ladder: the seed-point at the base of the ladder of the spine.