Fifty is also half of 100, which has a similar meaning; the Writings tell us that when used together with 100, fifty represents an intermediate state. God rested on the seventh day of creation. That represents a state of holiness and tranquility that was preserved in the form of the sabbath. Holier still was the seventh sabbath, which happened every 49 days. The Israelites would follow that solemn day with the “feast of the seven sabbaths” on the 50th day, and for similar reasons had a jubilee year every 50th year. For these reasons, among others, “fifty” in the Bible is the completion of a cycle, and in most cases represents fullness or sufficiency.

Oil -- typically olive oil -- symbolizes the good that comes from celestial love. Celestial love is love of the Lord, the highest and purest love we can have. The good of celestial love is the desire to be good springing from celestial love: Wanting to do the Lord's will because you love Him. That's not a state many reach, even in heaven, but it's a beautiful goal. This representation makes sense based on the idea that the sun -- the source of all natural light and heat, and thus all natural life -- represents the Lord, the source of all spiritual light, heat and life. Burning oil was the most pure fire available in Biblical times, thus the closest representation of the sun people could create.