When the משכן was completed, the נשיאים brought special קרבנות and gifts. One of the things they gave were six wagons and twelve oxen to pull them. These would be used by the לויים to help transport the משכן when they traveled.
Question
The משכן had many big, heavy parts that had to be transported. Four of the six wagons were used to transport the 48 קרשים, and more. The גמרא describes how the קרשים were piled up, and hung over the sides of the wagons, with a לוי walking alongside it, to ensure that they didn’t slip off while traveling.
Why didn’t the נשיאים just give more wagons?
Answer
Every part of the משכן was exact and precise. This is because every part of the משכן had to be used to its fullest capacity. If there was something not being used, it would make it extra and unnecessary. This is why the נשיאים gave exactly six wagons and twelve oxen. Since the משכן could be transported in this manner, giving anything more would have been extra and unnecessary.
Life Lesson
We must make sure to fully utilize the time and talents and all of the resources that Hashem gives us, to build our spiritual משכן, and make this world a דירה בתחתונים for Him.
Further discussion
How did limiting the amount of wagons help the לויים do their job? (See אות ז in the שיחה)