출애굽기 26:15의 주석

ועשית את הקרשים AND THOU SHALT MAKE THE BOARDS — It should be said: “Thou shalt make boards” (without the definite article), the same form which is used of each of the other things (parts of the Tabernacle)! What is the force of the term, “the boards?” It speaks of those boards that already existed as being designated for that purpose. For our father Jacob had planted cedars (shittim-trees) in Egypt and when he died be bade his sons carry them up with them when they would leave Egypt. He told them that God would once command them to erect a dwelling of shittim-trees in the wilderness. “See” — added he — “that they be ready in your possession!” (cf. Rashi on Exodus 25:5). That is what the Babylonian embodied in his liturgical composition: The plant of those who had been admonished by their father Jacob grew up rapidly to become the cedars for the beams of our House (the Tabernacle), which refers to the fact that they had been admonished that they (the cedars) should be ready in their possession in advance (before they were needed).

עצי שטים עומדים. Not arranged horizontally as such boards are normally arranged in buildings of a secular nature.

ועשית את הקרשים למשכן. "You shall construct the boards for the Tabernacle." The word למשכן indicates that only the coverings qualified for the term "Tabernacle," not the boards supporting the tent.