And the nethermost chamber [was] five cubits broad
The nethermost row of them, which were upon the first floor:
and the middle [was] six cubits broad, and the third [was] seven cubits
so that the middlemost was a cubit larger than the lowest, and the highest a cubit larger than that: the reason of which was,
for without [in the wall] of the house he made narrowed rests round
or rebatements; the thickness of the wall, as it was raised, became narrower at the height of every five cubits; thus the wall being supposed to be six cubits broad, as in ( Ezekiel 41:5 ) ; when it came to be five cubits high, it was narrowed a cubit, which left a projection, rebatement, or bench for the beams of the first chambers to be laid upon, which made the second row of chambers broader by a cubit; and the same being observed in the next story, made the highest a cubit broader than the middlemost: and this was done,
that [the beams] should not be fastened in the walls of the house;
or be inserted into them, which could not be done without making holes in it; and these holes could not be made without an iron instrument, and which was not to be used, as the next words show; whereas by the above method the beams of the chambers could be laid upon the buttresses, benches, or rebatements left, without the use of any: the gradual enlargement of these chambers, as they rose higher, may denote the enlargement of the church of God, both as to numbers, gifts, and grace, the nearer it comes to the heavenly state, as in the spiritual and personal reign of Christ.