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.

In John 2:6, 7, the water pots signify external knowledges; which may be filled with truths. They also signify all those features of the Word, and so of the Jewish church and its worship, which were signified and represented by Divine things in the Lord and from the Lord. (Apocalypse Explained 376[29])

(Odkazy: Arcana Coelestia 3068)