No, the scripture is speaking of the head stone, the most prominent part of the structure.
Foundations do not have a single corner stone, they have at least four of them.
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I can see that what you say may be true. Yet, how does one build a building from the top down...?
Gotta give this post also some extra consideration.
G’night.
But I’m sure you know there is a MAIN one: the place where the entire building is started from.
The coordinate system for laying out land in Utah originates at the cornerstone of the Temple in SLC.
http://en.wikipedia.org/wiki/Downtown_Salt_Lake_City