Comparing Olive Oil to Christ’s Blood
You may never look at blessings the same again. This chart clearly suggests that olive oil is symbolic of Christ’s blood. Which makes perfect sense. Christ’s blood heals us on so many different levels.
Also notice that both olive oil in blessings and water from the sacrament are blessed by holders of the priesthood first. (olive oil is consecrated and the water is blessed) Only then can they be effective as part of the ordinance.
Olive oil was used for a lot of things. You can eat olives, use the oil for medicine, soap, and you can burn it for light.