Fire
Fire, in the spiritual sense, can mean either love or hatred depending on the context, just as natural fire can be either comforting in keeping you warm, or scary in burning down your house. Our language reflects this, too -- we use concepts like a smoldering hatred or a burning love. So fire signifies a love, either a good love of the neighbor and to the Lord, or, in a bad sense, selfish love of oneself that, if unchecked by conscience, leads to hatred of anyone that opposes it.
Heaven and Hell #116
116. THE SUN IN HEAVEN
In heaven, neither the sun of the world nor anything from that sun is seen, because it is wholly natural. In fact, nature has its beginning from that sun and whatever is produced by means of it is called natural. But the spiritual, in which is heaven, is above nature and quite distinct from what is natural, nor is there communication between the two except by means of correspondences. What the distinction between them is may be understood from the things said before about degrees (38), and what the communication is from the things said in the preceding two sections about correspondences.