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.

2954. 'I will give the price of the field, accept it from me' means redemption as regards the truths of the Church which come from the Lord. This is clear from the meaning of 'giving the silver' as redeeming by means of truth, dealt with above in 2937, for 'silver' means truth, 1551; from the meaning of 'the field' as the Church, and also the doctrine of truth, dealt with in 368, 2936; and from the meaning of 'accept it from me' as a willing response with those who belong to the Church. That response involves a belief that redemption comes from the Lord alone. As for what redemption is, it is the same as reformation and regeneration, and therefore being delivered from hell and being saved. The redemption, or reformation and salvation, of members of the spiritual Church is effected by means of truth, whereas that of members of the celestial Church is effected by means of good.

[2] The reasons why have been stated in various places already - that spiritual people possess no will at all for what is good, but instead have been provided with an ability to understand what good is. The understanding of what is good is primarily called truth, and indeed the truth of faith, while the willing of it and from this the doing of it is called good. Spiritual persons therefore, by means of an understanding of good, or what amounts to the same, by means of truth, are led on to a will for what is good, or what amounts to the same, to good. They are not led on to any will for what is good from anything that is their own, since all will for what is good has with them been destroyed, 895, 927, 2124. Instead they are led on to a new will which they receive from the Lord, 863, 875, 1023, 1043, 1044; and when they have received this new will they specifically are called the redeemed.