There were three stories of side chambers built around the Temple on three sixths; what, therefore, is called in the authorized aversion a middle Clamber was really the middle story of those three. The Hebrew word is yatsang. They are thus described in First Kings vi, 5, 6, 03: And against the wall of the house he built chambers round about, against the walls of the house round about, both of the temple and of the oracle: and he made chambers round about. The nethermost chamber was five cubits broad and the middle was six cubits broad, and the third was seven cubits broad: for without in the wall of the house he made narrowed rests round about, that the beams should not be fastened in the walls of the house. The door for the middle chamber was in the right side of the house: and they went up with winding stairs into the middle chamber, and out of the middle into the third.
These chambers, after the Temple was completed, served for the accommodation of the priests when upon duty; in them they deposited their vestments and the sacred vessels- But the knowledge of the purpose to which the middle chamber was appropriated while the Temple was in the course of construction, is only preserved in Masonic tradition. This tradition is, however, altogether mythical and symbolical in its character, and belongs to the symbolism of the Winding Stairs, which see.