The porch, or vestibule, according to Keil, appears to have been entered by a folding door of two leaves, each three cubits broad, which were attached to two side pillars five cubits broad, and met in the middle, so that the whole breadth of the porch front was six cubits, or, including the posts, sixteen cubits.
The measurements in Ezekiel 40:49 of the length of the porch (from east to west) twenty cubits, and the breadth (from north to south) eleven cubits, he harmonizes with this view by assuming that the pillars, which were five cubits bread in front, were only half that breadth in the inside, the side wall dividing it in two, so that, although to one entering the opening was only six cubits, the moment one stood in the interior it was 6 cubits + 2 x 2.
5 cubits = 11 cubits. Kliefoth, however, rejects this explanation, and understands the three cubits to refer to the portion of the entrance on either side which was closed by a gate, perhaps of lattice-work, leaving for the ingress and egress of priests a passage of five cubits.
In this view the whole front of the porch would he 5 cubits of passage + 6 (2 x 3) cubits of lattice-work + 10 (2 x 5) cubits of pillar, equal in all to 21 cubits. Dr. Currey, in the 'Speaker's Commentary,' includes the three cubits of door in the five cubits of post, and, supposing the temple entrance to be ten cubits, makes the whole front to have been twenty cubits.
We prefer Kliefoth's opinion.