After having received the instructions from G-d for the erection of the Mishkan (Tabernacle), Moshe now passes these instructions on to the Children of Israel.
Every aspect of the building of the Mishkan itself and its vessels is given over in detail. And every detail has significant meaning.
One of the most common materials used in the building of the Mishkan and its vessels was shittim (acacia; from a cedar tree) wood. The walls of the tabernacle, parts of the ark, the altar, and the table were all made from this wood.
What can we learn from the use of this wood?
The Midrash explains that when the Jewish people arrived in Egypt, Yakov (Jacob) saw through prophecy that in the future, the Jewish Nation would build a Mishkan in the desert, and would need these types of trees, so he planted them in Egypt.
Yakov knew that every step the Jewish people take is for a specific purpose. Their stay in Egypt, or in any other exile, was not arbitrary, but had a specific rectification to be accomplished. What Yakov did was a microcosm of Jewish history. During each situation, the Jews not only attempted to achieve the purpose of their present exile, but did everything possible to look towards the next step.
The Jewish people do not exist in a vacuum. Every move we do has ramifications and effects for the future. If we do good, we have come one step closer to our goal of bringing G-d’s presence to the world. If we do bad, G-d forbid, we have pushed ourselves further away from G-d.
Yakov knew that the Egyptian exile was to make or break the Jewish people; while many were made (the people who left) many were also broken (the eighty percent who died during the plague of darkness). It is for this reason that our sojourn in Egypt was called an iron crucible (Deut. 4:20). Knowing this, Yakov set up the means which would exemplify the purpose of the Egyptian exodus — to make a dwelling place for G-d — before the Jewish people were even enslaved in Egypt. Yakov did this because he saw Jewish history not as an unrelated series of events that happened to a nation, but a pattern of events orchestrated by G-d in response to the deeds of this nation. And that all this was done — punishments and reward, redemption and exile — for the ultimate goal.
In this light, Rabbi Shamshon Raphael Hirsch explains that the shittim wood was chosen because of its ability to grow and blossom with renewed vigor, much as the Jewish people have had to do.
We must live as Jews with one eye towards the future and one eye on the past.