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.

10221. 'Half a shekel according to the shekel of holiness' means all forms of truth springing from good. This is clear from the meaning of 'half' as all; and from the meaning of 'a shekel' as truth springing from good. The reason why 'half' means all is that half a shekel consisted of ten gerahs or obols, and 'ten' means all, 4638, and also remnants, 576, 1906, 1988, 2284, which are the truths and forms of good present with a person, stored away by the Lord in the more internal parts of him, 5135, 5342, 5897, 5898, 7560, 7564. The reason why 'a shekel' means truth springing from good is that it was a weight of silver and also of gold, and 'silver' means truth and 'gold' good. But the amount of truth springing from good and of good coming through truth is determined by the number of gerahs or obols to a shekel. The shekel, being essentially a weight, means the amount; and when it is called 'the shekel of holiness' the amount of truth and good is meant, the reason for this being that truth and good are what are called holy because they come from the Lord who alone is Holy. For more about the shekel and the meaning of it, see 2959.