(Midrashic and botanical evidence of the source of the lumber used in building the mishkan; December 2007)
In Exodus 26:15 (parshat Terumah), we read that the boards for the wall that surrounded the Mishkan (Tabernacle) were to be made from ”upright acacia trees” (in Hebrew, “atzei shitim omdim”). However, the acacia trees available to the Jewish people at the time were only those that could be found in the Sinai desert. The sparse water supply in the desert limits these species to a short, gnarled growth form that would never have been called upright. To see an example of an Egyptian desert acacia, go to:
However, the dimensions that are specified for these boards in Exodus are far larger than anything that could be cut from such a tree. The boards are to be 1 x 1.5 x 10 cubits in size. Assuming, as most authors do, that a cubit (Hebrew ‘amah’) is approximately 18 inches, we find that the boards were 18 x 27 inches (45 x 68 cm) in cross-section, and 15 feet (nearly 5 m) long. The difficulty of obtaining such lumber in the desert was obvious to the Torah’s ancient readers, who were intimately familiar with the conditions of life in the various ecosystems of the Middle East. As is often the case, the midrash (collection of homilies) provides an explanation. Midrash Tanchuma, a work attributed to a rabbi of the same name, describes a tradition that the patriarch Jacob collected saplings from a place in the northern Jordan Valley called Migdal Tzava’ya (“The Dyers’ Tower”; the Talmud refers several times to this location as a center of cloth making and dying.) to take with him to Egypt. He is said to have recognized prophetically that his descendants would need these trees centuries later to build the Mishkan. Jacob’s son Joseph rose to high public office in Egypt. The midrash further states that Joseph instructed his own sons Ephraim and Menashe to plant these trees in Egypt, ensuring a ready source of lumber for the future.
Several tantalizing lines of evidence offer support for this tradition. The Jerusalem Talmud (Taanit 1:6) reports a request for a rabbinic ruling on the permissibility of cutting wood from the acacia grove at Migdal Tzava’ya. Rabbi Chananya responded that the longstanding custom to leave these trees unharvested should be respected. Today, Migdal Tzava’ya is located in northwestern Jordan. Remarkably, the local Arab population continues to regard the acacia trees of this site as sacred. But how could such large boards be cut from acacia trees? The acacias of Migdal Tzava’ya are of a different species from the desert acacias. In the moister climate of the Jordan valley, Acacia albida, the white or winterthorn acacia provides a dramatic contrast to the desert acacia. The white acacia is an excellent candidate for the Torah’s term “upright acacia trees.” Its trunk is straight and tall, often exceeding 30 feet in height. A dramatic example of a 52-foot tree at the San Diego Zoo can be seen at
The original grove at Migdal Tzava’ya has apparently spread since Talmudic times. Acacia albida can now be found on both sides of the Jordan river, in both Jordan and Israel. Today, visitors to the Galilee can view and contemplate trees that may be descendants of the same ones that Jacob collected to carry into exile in Egypt.
A puzzling detail in the story recounted by the Midrash Tanhuma is an apparent indifference to the identity of the ‘shita’ referred to in Exodus 26:15. The midrash shifts back and forth, seemingly at random, between the terms ‘shita’ (acacia) and ‘erez’ (cedar), as if the two were synonymous. Yet even the unfamiliar observer can easily distinguish these unrelated trees, which grow in very different environments. Certainly Rabbi Tanchuma, who lived in much closer proximity to nature than most of us do today, would have recognized this problem, if it really is a problem. But Talmudic classification of living things is a topic for another issue of Torah Flora.