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.

8410. 'Eating bread to the full!' means that in that situation they enjoyed the good of lower pleasures, as much as they wished to have. This is clear from the meaning of 'eating' as making one's own, dealt with in 3168, 3513 (end), 3596, 4745, and also as enjoyment, 7849; from the meaning of 'bread' as the good of heavenly life, and in the contrary sense the good of natural life separated from heavenly, thus the good of lower pleasures (in the spiritual sense 'bread' means the chief thing that nourishes the soul and maintains its spiritual life, that chief thing being the good of love, as heaven's life demonstrates, which consists wholly of that good. But in the contrary sense 'bread' is used to mean the chief thing that nourishes those in hell and sustains their life, that chief thing being the evil of self-love and love of the world, as hell's life demonstrates, which consists wholly in that evil. To those in hell that evil is good, for to them nothing is more delightful or sweeter; and it is this that is meant here by the good of lower pleasures); and from the meaning of 'to the full' as, as much as they wished to have, since the will is what is filled with good if people are good, or with evil if they are evil.