The Midrash questions the specific use of shittim wood for the beams of the Mishkan. Chazal respond that Hashem has chosen to teach a lesson regarding the proper derech eretz one must model when building a house or when undertaking any endeavor which affects others. Hashem chose shittim wood which comes from a barren tree. Likewise, when we build, we should use wood which originates from a tree which does not produce fruit.
This Midrash is noteworthy. The Mishkan is the major source of holiness in this world. Yet, its construction may not affect any other form of “life,” even inanimate life. How much more so should we be considerate of the sensitivities of others when we embark upon a new venture. When building an edifice for Torah, whether it be a place for Torah study or prayer, we should construct it of components which do not infringe upon others. The money and materials must originate from reputable sources. One should never identify himself or his activities with financial sources of questionable repute.
