Compared to Parshat Terumah, where the verse speaks about the construction of the Tabernacle from the voluntary contributions of each individual, "from every person whose heart inspires him to generosity, you shall take My offering," in Parshat Tetzaveh, we have a commandment! "And you shall command the children of Israel" - no longer relying on the voluntary contributions of the individual but needing to command them. There is a difference between things brought as a donation and remaining, such as gold, silver, blue, and purple yarn, all of which stay in the Tabernacle for many years. This is in contrast to Parshat Tetzaveh, which speaks of perishable items. For example, the oil placed in the menorah, every day, fresh oil must be placed. The natural inclination of people to donate is, for example, to build a building on which the donor's name will be written. But to pay for lunch that exists today and will not exist tomorrow is more complicated. Here, a commandment is needed since Parshat Tetzaveh speaks of a low level of readiness for people to participate in holiness. No, because what does the verse say? "and they shall take to you pure olive oil." That is, you initially give a command. Still, you reawaken the spontaneous generosity of the children of Israel, "and they shall take to you pure olive oil, crushed for lighting, to kindle the lamps continually," so there is also an educational strategy. We start with a command and slowly.
He was returning to generosity. There is an addition in this portion that we still need to find in Parshat Terumah: the incense altar. There is incense in the Tabernacle; what does this incense provide? It gives a good smell. That is, man needs subjective stimuli to connect him to the holiness. He needs priestly garments for honor and glory. There is a connection with the holiness that comes through the action of imagination and the smell of the clothes; all these are a novelty of the Parshat Tetzaveh for someone whose intellectual work is not satisfying, he also needs the action of imagination.