From Dan Lifshitz: At the beginning of the Parshat Tetzaveh, the Jews are commanded to bring the purest olive oil as fuel for the lamp in the Tabernacle. Rashi explains that the purest olive oil is required for the lamp, but not for the flour offerings brought in the Tabernacle.  What is the significance of this ritual detail?
R’ Baruch Simon, quoting from the Chasam Sofer, explains that this rule runs contrary to how one would act at home.  A person would use the purest, best tasting olive oil in food, and use a lower grade of oil as fuel, where the taste doesn’t matter.  However, in the Tabernacle, the best grade was used for the lamp and a lesser grade for the equivalent of food.  The lamp symbolizes wisdom, Torah and the life of the spirit while the flour offering symbolizes material things. This detail regarding which oil should be used for which purpose in the Tabernacle is actually teaching a broad lesson about priorities in life. Often, the inclination is to seek out the best and to expend the most effort in material matters, while settling for “good enough” in the spiritual realm.  The olive oil is teaching us that the opposite outlook is the proper one.