"Fire" is not just for hell. Love is a more powerful fire.
Jesus said: Lc 12:49 "I came to cast fire upon the earth; and would that it were already kindled! 50 I have a baptism to be baptized with; and how I am constrained until it is accomplished!"
If Jesus' fire is love. It is consuming fire that draws us to the furnace of His Sacred Heart and transforms us into His likeness. This fire is the Holy Spirit. We should desire Him with all our hearts. If we desire it, we enter it without counting the cost.
Many mystics speak about the experience of divine love as a fire.
St. Catherine of Siena: "If you are what you should be you will set the whole world on fire"
St Teresa experienced this fire increasing as she approached the inner mansions unto union with God. She said that God wants to give all the gift of the blazing unitive fire but most put limits to Him. Limits: fear of the fire because deep inside we dont trust God as He begins to work in our soul. Lack of witnesses that can give us hope that this fire is real.