was good and life so full hope was not necessary and therefore forgotten.

Religious imagery comes into the landscape in chapter three when Simon feeds the littluns fruit that he hands down from a tree. It is meant to evoke the biblical story of Christ feeding the multitude. Immediately after this Christian deed, Simon retreats into nature; he enters a hidden clearing and communes with nature with imagery that evokes a cathedral when

the candlebuds stirred. Their green sepals drew back a little and the white tips of the flowers rose delicately to meet the open air.

At the chapter's end, the candlebuds's "scent spilled out into the air and took possession of the island." The description calls to mind the use of incense in Catholic ritual as a symbol of prayers rising to Heaven.

The forces of good and evil are generally divided up into the forces within the boys.  Piggy and Ralph are trying hard to help the boys govern themselves and to organize to help effect a rescue and to make sure people are fed and accounted for.

Simon, who also serves as the Christ figure, is aligned with no one, shows particular care for the little ones, and eventually has the epiphany and understands that the evil forces are really those within the boys, the beast is within.  Soon after this realization he is killed, of course it is also notable that his vision comes after wandering off alone into the wilderness.

Jack and to an even larger extent Roger represent the evil within boys.  Particularly Roger as he reaches the point where he has no issue with killing and does it with glee, he really represents evil by the end of the story.

This is an excellent question regarding Golding’s novel, which can be interpreted as a religious and moral allegory.

The island as a whole represents the Garden of Eden, and the immoral acts of the boys are a form of corruption; though Simon does find a dead pilot on the mountain, the land can generally be seen as untouched and hence pure, like the Garden of Eden before the sins of Adam and Eve. According to the Hebrew Bible's book of Genesis, the Garden of Eden is a place of holy paradise; similarly, the children are in awe of the island’s natural beauty and bounty.

Simon, who continues to uphold morality until he is murdered, represents the death of Christ. Both Simon and Jesus are inherently good; defend the weak (Simon protests to Piggy’s mistreatment); wander in the wilderness to contemplate the evil of man; and can be viewed as sacrifices as they died in the effort to save humans from themselves. Simon comes down the mountain to inform the boys that what they thought was "the beast" is in reality a dead parachutist; he recognizes how fear over the alleged creature has brought evil out of the boys. The brutal situation in which Simon is beaten to death, parallels that of Jesus dying in immense pain on the Christian cross.

Before Simon’s death, the severed and rotting pig’s head speaks to him as the Lord of the Flies, confirming the evil Simon believes is contained within the boys:

You knew, didn’t you? I’m part of you? Close, close, close! I’m the reason why it’s no go? Why things are what they are?

Here, and in the deaths of Simon and Piggy, the author emphasizes that the real beast is contained within the boys themselves. The phrase "the lord of the flies" is a literal translation of the Hebrew word Beelzebub, meaning the Devil. According to Abrahamic religions, Satan was a fallen angel. The boys' fall from grace can be seen as the killings of Simon and Piggy. Parallels are established between the severed boar head and the Garden of Eden story: the pig’s head represents evil, just as the serpent tempted Eve, who subsequently tempted Adam, to eat the forbidden fruit (contains the knowledge of good and evil). The apple (forbidden fruit) in the Genesis story symbolizes sin, just as the destroyed conch represents the breakdown of the island society and its associated evils.

The issue of redemption is a trickier one in Golding’s novel. Some literary experts argue that there is no redemption in the novel, that it instead conveys the Biblical theme that humans are evil by nature, and that redemption is only attainable through faith in God. A religious individual could argue that Simon will go to heaven, as he lived according to the Bible’s teachings. We can also look at the novel’s conclusion: how does the story end? Ralph flees from Jack and the other boys and discovers a British naval officer. The rest of the boys join Ralph in telling their story, and several of them start to cry. Thus, the end of the novel can be seen as the beginnings of redemption, as the boys are beginning to recognize the extent of their evil actions. They will return to society, live as normal children again, and have the chance to redeem themselves through their actions; just as people are forgiven for their sins when they are confessed to God.

Whenever you're talking religion in Lord of the Flies, you're talking about Simon. And the key chapter for religious imagery is the one in which he climbs the mountain to discover that the beast is in fact just a dead parachutist, shot down in the war raging back in the real world.

The parachutist himself represents a fall from grace (as perhaps, do the boys themselves, falling in a crashed plane onto the island). Golding deliberately moves, at the end of Chapter 5, from the wailing littluns to the parachutist's descent: civilisation on the island has very clearly descended towards savagery. Here's the parachutist, described just after the littluns have cried:

There was a sudden bright explosion and a corkscrew trail across the sky; then darkness again and stars. There was a speck above the island, a figure dropping swiftly beneath a parachute, a figure that hung with dangling limbs. The changing winds of various altitudes took the figure where they would.

This figure terrifies the boys, and Simon, of course, is their saviour - or he would be, if they didn't kill him (sound Christ-like? It's supposed to). Simon's knowledge of the parachutist would save the boys from fear; but they kill him out of fear, thinking he's the beast. And as he dies, he's uttering the truth - which, ironically, could be both a description of the parachutist and a reference to Christ's crucifixion in the Bible:

Simon was crying out something about a dead man on a hill.

Simon, the redeemer, is himself redeemed by nature once his attempted redemption has failed. In a beautiful description, Golding has the dead body of the boy taken back into the bosom of nature - a kind of redemptive calm after the horror of his death:

The water rose further and dressed Simon's coarse hair with brightness. The line of his cheek silvered and the turn of his shoulder became sculptured marble. The strange, attendant creatures, with their fiery eyes and trailing vapours, busied themselves round his head. The body lifted a fraction of an inch from the sand and a bubble of air escaped from the mouth with a wet plop. Then it turned gently in the water.

Notice, of course, the bright creatures around Simon's head. They'd look a bit like...  a halo.

Religious imagery abounds in Lord of the Flies. First and foremost, there is the island on which the boys are stranded. Lush and verdant, it seems like Paradise from the Book of Genesis. But it isn't very long before sin enters this Garden of Eden and the boys, through their sinful behavior, effectively expel themselves from Paradise.

Then we have the character of Simon, a kind of Christ-like figure. A gentle, thoughtful soul prone to communing with nature, Simon stands apart from the other boys, both literally and figuratively. His wanderings in the jungle can be compared to Christ's walk in the wilderness. They highlight the sense in which the goodness and innocence displayed by Simon have no place within the atavistic, sinful society constructed by the other boys.

The brutal manner of Simon's death also has parallels with Christ's crucifixion. Savagely attacked and killed by the other boys as part of a crazed pagan ritual that quickly gets out of hand, Simon is sacrificed on the altar of evil.

Golding uses religious imagery primarily as a means of giving depth to his story. He doesn't simply want to present us with a tale about a group of posh English schoolboys crash landing on a desert island and descending into savagery; he wants to give us a morality tale, which given that it takes place among boys raised in the Christian tradition, inevitably involves the use of religious imagery drawn from that tradition. In doing this, Golding infuses his story with a universal message.