Emerald Tablets - Sounds Like what Ra says about the use of the sarcophagus in the great pyramid

Raised I high over the entrance, a doorway, a gateway leading down to Amenti.

Few there would be with courage to dare it; few pass the portal to dark Amenti.

Raised over the passage, I, a mighty pyramid, using the power that overcomes Earth force (gravity).

Deep and yet deeper place, I, a force-house or chamber; from it carved I a circular passage reaching almost to the great summit.

There in the apex, set I the crystal,

Sending the ray into the "Time-Space," drawing the force from out of the ether, concentrating upon the gateway to Amenti.

Other chambers I built and left vacant to all seeming, yet hidden within them, are the keys to Amenti.

He who in courage would dare the dark realms, let him be purified first - by long fasting.

Lie in the sarcophagus of stone in my chamber.

Then reveal I to him the great mysteries