Fire is a motif that can represent many different things within a story. Fire can symbol a rebirth within a character as a ‘baptism by fire’ seen as cleansing their past and a new step forward. The legend of the Phoenix is a classical example of this motif. This is heavily used in fantasy series, an example being Gandalf. Gandalf fought the Balrog, a demon of fire, and was brought down killing the beast. Instead of dying forever, he returned as a more powerful, clean version. He was reincarnated from Gandalf the Grey to Gandalf the White.
Fire can also represent destruction or insanity. A character that has a penchant for fire is assumed to be volatile, destructive, and can quite often try to act cool but lose control dangerously. And example of this would be Tibalt from Romeo and Juliet, or Firebenders from Avatar The Legend Of Aang, most specifically Azula. The love of fire shows that it can be a passionate person who may not be evil but cause carnage wherever they go.
Fire may also represent hope, if it is described as a tamer flame or lighter in color. This has been so for a long time, as in Ancient Greek tales Prometheus steals fire from the Gods and gives it to humanity. For this he and humanity are punished. He is subjected to torture at the hands of an eagle, and humanity was given Pandora’s box. Opening the box unleashed horrors and plagues and hardships onto the world. However humanity still had fire, and there was one other thing left in the box. Hope. Hope was left to humanity. The light in the tunnel, the guiding torch in a cave, these show the hope of wanting to leave and the last protection from darkness. The light from the fire protects us from the darkness and unknown of the night as a last defense, like hope was left to protect us from the horrors of life.
Fire also can be a motif for home and the hearth. The warmth of fire is soothing and protects us, as it is found within the walls of home. The same idea when a group goes camping, and everyone ends up huddled by the fire, which in stories is the typical place people reveal secrets to their past, maybe because the fire reminds them of home. Fire is essential to life providing warmth, cooking, and cleansing water. The power of fire in our lives helps remind us of home and can even create a motherly feel.