“Washing” in the Bible represents purification - unsurprisingly! Washing dirt from the skin symbolizes using true ideas from the Lord to remove evil desires and false ideas from our minds. This is the reason that washing was such an integral part of ritual; cleaning the body to perform physical acts of worship - something with no actual spiritual value - is symbolic of repenting our evils and falsities as part of worshiping the Lord.

10747. Since love is the fire of life and what the life in anyone is like is determined by his love, it may be seen from this what heavenly fire is and what hellish fire is. Heavenly fire consists in love to the Lord and love towards the neighbour, while hellish fire consists in self-love and love of the world and in the consequent craving which goes with all the evils that pour out of these kinds of love as their source.