The inside of the Tabernacle, the desert worship space of the Israelites, is 30 cubits long. (This is worked out from directions for various components, described in Exodus 26-27.) An inside covering is composed of ten panels of “twisted linen, and indigo and purple and crimson, with cherubim, designer’s work,” each measuring 28 cubits by 4 cubits (Alter’s translation; citation below). Eleven goat-hair panels of 30 cubits by 4 cubits create an additional covering over the whole construction. (Explicit instructions in Exodus 26:1 and 26:7).
The inside coverings are joined so “that the Tabernacle be one whole” (Exodus 26:6).
26:6) that the Tabernacle be one whole
This phrase leads Abraham ibn Ezra to muse over how unity in the greater world is constituted by an interlocking of constituent parts that become a transcendent whole, as in the unity of microcosm and macrocosm. One need not read this section homelitically, as he does, in order to see the power of summation of this particular phrase.
— Alter, Robert. The Five Books of Moses: A Translation with Commentary. (NY: Norton, 2004)
The Stone Chumash (citation and more information) does take the homelitical approach, however, noting in addition symbolism uniting “the Holy of Holies” with “the Holy”:
By covering the walls and air space of the building this Cover unified everything that was inside the Tabernacle, meaning that the Ark, Table, Menorah, and Golden Altar were not unrelated vessels, each performing its own separate task, but were parts of a united whole.
Indeed, this represents the Torah’s philosophy of Jewish life. Learning, ritual, business, and so on do not spin in separate orbits, but work together toward a single spiritual goal. In this sense, the first covering was the Tabernacle, because it joined them all together.
According to Or HaChaim, the ten curtains of the Tabernacle symbolized the ten sayings with which God created the world [Avot 5:1]….
…Thus the concept that the Tabernacle shall be one is an indication that all elements of Creation — Heavenly and human alike — should work together toward a common goal.
— Stone Chumash
Alter notes that the goat-hair layer offered “the capacity to keep out bad weather.” Kedushat Levi takes a far different approach: The inner coverings, which are made of tekhelet (the special blue also used in tzitzit and associated with the divine), represent God’s essence; the courser outer covering, having two “extra” cubits, represents a “diluted” version of God’s light — “the original light…too bright for the human eye to behold” (p. 473).
The measurements and colors inspire a variety of other comments….
As part of NaBloPoMo (National Blog Posting Month), a cousin of NaNoWriMo (National Novel Writing Month), “A Song Every Day” plans thirty daily posts with some connection to the number 30.