“You shall command the people of Israel that they bring to you pure beaten olive oil for the light, that a lamp may regularly be set up to burn. In the tent of meeting, outside the veil that is before the testimony, Aaron and his sons shall tend it from evening to morning before the LORD. It shall be a statute forever to be observed throughout their generations by the people of Israel” (Exodus 27:20 ESV)

This oil was used to keep the 7 light, golden candle stand ever-burning in front of the table with the 12 loaves of bread (testimony). An Aaronic priest had to work the night-shift to keep it burning. Jesus is the fulfillment of this temple worship. He is both Light of the World and Bread of Life. And we are to keep the light shining on His Testimony in a dark world.