Albert Barnes Commentary Ezekiel 41:3

"Then went he inward, and measured each post of the entrance, two cubits; and the entrance, six cubits; and the breadth of the entrance, seven cubits." — Ezekiel 41:3 (ASV)

He went inward - Toward the holy of holies. It is not said, “he brought me in,” but “he went in,” because the holy of holies was not to be entered even by a priest like Ezekiel, but only by the high priest once a year. So the “angel” enters and announces: the measurements.

The post of the door - On either side of the entrance was a pillar, the two together making up two cubits. The first measurement of the door was from “post to post,” six cubits; and the second measurement, the “breadth of the door,” was the breadth of the actual doors that shut off the holy of holies (Ezekiel 41:23), and which may have been so hung that each of the “posts” projected half a cubit beyond the hinge of the door (which opened inward), to secure the complete closure of the holy of holies.