The recipe for the oil to be used in anointing a priest and the articles used in the tent of worship is given in Exodus 30:23-25.
“Take the finest spices: of liquid myrrh 500 shekels, and of sweet-smelling cinnamon half as much, that is, 250, and 250 of aromatic cane, and 500 of cassia, according to the shekel of the sanctuary, and a hin of olive oil. And you shall make of these a sacred anointing oil blended as by the perfumer; it shall be a holy anointing oil.
Some versions translate these ancient measurements into modern equivalents. For example:
Mix a gallon of olive oil with the following costly spices: twelve pounds of myrrh, six pounds of cinnamon, six pounds of cane, and twelve pounds of cassia. Measure these according to the official standards. (Exodus 30:23 CEV)
We are not given specific reasons for the ingredients, but presumably the olive oil was used as a base because it is the most commonly available oil in Israel.
The Lord told me the ingredients it was representing the “sweet savour of God” and the oil is the body of Christ. Put the two together mix in prayers from the elders and you have a powerful oil!!
That’s why it was so holy and guarded and only the priests were to have it and use it. That’s why they couldn’t use it on the unsaved people or “common people” and that’s why no one who was common could touch anything the oil anointed cuz it would make them holy and they weren’t deserved of it and it would cause them death!!