John Gill Commentary Exodus 26:20

"And for the second side of the tabernacle, on the north side, twenty boards," — Exodus 26:20 (ASV)

And for the second side of the tabernacle the north side
The direction of the tabernacle was east and west; at the east end was the entrance into the holy place, and at the west end the holy of holies; and the two sides were north and south; and as on the south side, so on the north

[there shall be] twenty boards :
just the same number as the laws of building required.