‘And the temple and the sanctuary had two doors, and the doors had two leaves each, two turning leaves, two leaves for the one door and two leaves for the other.'
There were two doors in both the entrance to the holy place and the entrance to the holy of holies, and each of those doors divided in two so that they could be turned back on themselves. Thus it was possible to enter by just opening one half of a door leaving a small gap to pass through. This was to preserve the holiness of these places and to stress their inaccessibility except to those given access when the time was right, in the case of the holy of holies but once a year for the High Priest.