You shall make it hollow, with boards. As it has been shown you on the mountain, so shall it be made.
As God intended in the tabernacle to manifest his presence among his people, so there they were to pay their devotions to him, not in the tabernacle itself (into that only the priests entered as God's domestic servants), but in the court before the tabernacle, where, as common subjects, they attended.
Commenting on Exodus 27:1-8
Hollow with boards shalt thou make it,.... The frame of it being made of boards of shittim wood, there was nothing within side but the grate, which was put within the square, down into the middle of it, and so was light of carriage; though the Targum of Jonathan, and other Jewish writers, represent this hollow as filled up with dust and earth, to answer...
Hollow with boards - It seems to have been a kind of frame-work, and to have had nothing solid in the inside, and only covered with the grating at the top. This rendered it more light and portable.