Parallel
Ezekiel 41:7
Brenton's English Septuagint · Berean Standard Bible
And the breadth of the upper side [was made] according to the projection out of the wall, against the upper one round about the house, that it might be enlarged above, and that [men] might go up to the upper chambers from those below, and from the ground-sills to the third story.
The side rooms surrounding the temple widened at each successive level, because the structure surrounding the temple ascended by stages corresponding to the narrowing of the temple wall as it rose upward. And so a stairway went up from the lowest story to the highest, through the middle one.