Saint John of Damascus gives us some insight into these passages that are often used to instill fear rather than love of God. He explains this fire as a condition where we will not be able to satisfy the desires we carry with us into death, those desires that we have put above our desire to be united with God out of love and to do His will. This absence of any satisfaction for these misguided desires leads us to the kind of suffering which is like being burned by fire. Isn't it the nature of suffering our inability to satisfy our desires?
We say that the torment is nothing other than the fire of unsatisfied passion. For those who obtained changelessness in passion do not desire God but sin. But there in that place the commission of evil has no place. For we neither eat nor drink, nor get dressed, nor marry, nor gather wealth, nor does envy or another evil satisfy us. Therefore, by desiring and not partaking of the things desired, they are burned by passions as if by fire. But those who desire the good––namely God alone, Who is and exists eternally––and who partakes of Him rejoice according to the intensity of their desire according to which they also partake of the Desired One.When we pass from this life to a heavenly life there will not be the means to satisfy those desires that we place such high priority on in our earthly life. We will not be able to find satisfaction in food, in fancy parties where we dress to look our best, in all the pleasures we can buy with money, in the superior status or power we have gained. Heaven strips us of what was pleasurable in our earthly life. There is only one desire that can be satisfied in this new life. That is our desire to be united with God in love. Without this as our overriding desire we will not find pleasure in heaven. There will be no way to satisfy any other desire.
According to Orthodox teaching the fire that torments is not a physical fire, but is a torment that comes from the inability our soul to direct its desire towards communion with God. One who cannot do this is imprisoned by his own action and his passions strike him like poisonous serpents. He will be surrounded by those he hates and separated from those he loves and who love him. He will always be seeking what can never be satisfied. Dumitru Staniloae says, "He falls into a sort of dreamlike existence in which everything becomes chaotic in a senseless absurdity, without any consistency, without any search for an exit out of it, without any hope for an exit."
Why does God leave a person in such a condition? Why doesn't he show himself with His divine light so one can see and depart from such darkness? The answer is that God is not an external reality that imposes itself but is offered to us out of love. This cannot be perceived except through an openness to love that is humble and full of desire for Him. It is based on a relationship. He who is bound up in lesser desires will not admit that such love is possible when he cannot offer such love in return. God therefore cannot make Himself evident as a loving Person in this case. Saint Isaac the Syrian says that hell is a punishment of love.
Satin John of Damascus writes:
He who desires receives. He who is good receives good things ... The righteous, by desiring and having God, rejoice forever; but the sinners, by desiring sin and not possessing objects of sin, are tormented as if eaten by the worm and consumed by fire, with no consolation; for what is suffering if not the absence of that which is desired? According to the intensity of desire, those who desire God rejoice, and those who desire sin are tormented.We cannot say that God punishes us with fire, but that it is our own misdirected desires that lead us to suffering that is like being burt by fire. To avoid the fire our primary desire has to be directed toward our love of God.
Here on earth when we incline our desire toward other things and obtain them even partially, we find pleasure in them. Over there, however, when "God will be all in all" (1Cor 15:28) and there will be neither food, nor drink, nor any bodily pleasure nor any injustice, those who possess neither common pleasures nor anything from God will suffer great pain that is not produced by God, but that we prepare for ourselves.
We must remember that Jesus, God incarnate, came for our benefit. He came out of God's love for all mankind to save us from the fallen condition we are in. He did not come to punish us. He came to transform us and to teach us that our earthly desires are misguided when substituted for our love of God our Creator. He loves us so much that He sacrificed His own life on the Cross to free us from our sinfulness, showing us the way through His Resurrection to be joined with Him in His kingdom with eternal life, and then sends the Holy Spirit to establish His Church on earth for our perfection in love. He is a God of love and only calls us to return that love. We can enjoy the pleasures of this world, all He created is Good, but only if we always give priority to our desire for His love and give thanks to Him for what we enjoy. If we replace this supreme desire with earthy desires, these will not be fulfilled when we enter into the heavenly realm. Lacking a desire for union with God, we will find ourselves separated eternally from His love, the only desire that can be satisfied after our bodily death.
Remember that Christ is within each of us. He resides in our heart. Make His love your desire.
New Testament references to the fire of damnation:
"every tree that does not bear good fruit is thrown into the fire" (Matt 3:10, Lk 3:9)
"His winnowing fan is in His hand, and He will thoroughly clean out His threading floor, and gather His seat into the barn; but He will burn up the chaff with unquenchable fire." (Matt 3:12, Lk 3:17)
"Therefore as the tares are gathered and burned in their, so it will be at the end of the age.... Will cast them into the furnace of fire. There will be ailing and gnashing of teeth." (Matt 13:40, 42, 50)
"It is better for you to enter into life with one eye, rather than having two eyes, than to be cast into hell fire." (Matt 18:9, Mark 9:47)
"If Your foot causes you to sin, cut it off. It is better for you to enter life lame, rather than having two feet, to be cast into hell, into the fire that shall never be quenched." (Mark 9:45)
"If anyone does not abide in Me, he is cast out as a branch and is withered; and they gather them and throw them into the fire, they are burned." (John 15:6)
"The devil, who deceived them, was cast into the lake of fire and brimstone where the beast and the false prophet are. and they will be tormented day and night forever and ever." (Rev 20:10)
"Anyone not found in the Book of Life was cast into the lake of fire." (Rev 20:15)
"The cowardly, unbelieving, abominable, murders, sexually immoral,sorcerers, idolaters and all liars shall have their part in the lake which burns with fire and brimstone..." (Rev 21:8)
Reference: The Experience of God, vol 6, by Dumitru Staniloae, pp 43-47