Book 1 begins with a prologue in which Milton states the purpose of Paradise Lost: to justify the ways of God to humans and to tell the story of their fall. Following the epic tradition, Milton invokes a heavenly muse to help him tell the tale. The muse he calls upon is the same one who inspired Moses to write part of the Bible, he claims. Milton uses the gift of the muse to explain what led to the fall of man, and he introduces the character of Satan, a former great angel in Heaven known as Lucifer. Satan tried to overthrow God's rule and banded together with other rebel angels to begin a civil war. They were defeated by God and cast out of Heaven and into Hell.
The story begins with Satan and the other rebel angels waking up to find themselves floating on a lake of fire in Hell, transformed into devils. Upset, Satan gathers the fallen angels together. They work to build a capital in Hell for themselves, Pandemonium, and form a council to debate waging more warfare against God. Satan and the other angels don't seem to recognize that it is only through God's permission that they were able to loosen the chains that bound them upon their arrival in Hell. God allowed it because he is all-knowing and all-seeing and intends to change their evil intentions into goodness.
Greek epics involved heroes, wars, and heroic acts. They usually began with the writer invoking a muse as his guide. By invoking a muse that inspired Moses, Milton places Paradise Lost in the same epic category as religious texts and signals that he is writing an epic in the tradition of the ancient Greeks. Milton echoes and mimics earlier Greek epics in a few ways. His lengthy introduction and naming of all of the fallen angels in Hell resembles an epic catalogue, a long list of soldiers found in epics like The Iliad and The Odyssey. Further, Milton portrays Satan as a military leader who assembles and commands his troop of fallen angels. This is similar to the ancient Greek epics that glorified war heroes and serves to paint Satan as a kind of idealized protagonist.
But rather than tell the tales of heroic men, Milton is dealing with issues of Heaven and Hell, God and Satan, and the fall of man. He also draws a distinct parallel between Satan's rebellion against God and man's disobedience to God.
By beginning Paradise Lost with a focus on Satan, Milton sets him up as the possible protagonist of the book rather than the antagonist. Though Satan realizes he has been defeated in his battle against God, his sense of pride doesn't allow him to ask God for forgiveness and reentrance into Heaven. Here, Milton hints at the idea that even though Satan thinks he has control of his own life and decisions, God is always one step ahead of his creations. Milton never makes clear if he wants his audience to empathize with Satan, but making him the hero of the epic would have been a risky decision in Milton's Christian era. Milton's audience would have been more likely to understand the complete power God had over Satan and that his battle was doomed to be futile. Contemporary audiences are more likely to see Satan as the sympathetic underdog of the story and to see God as rigid and unfeeling
With Satan sitting on an elaborate throne, the council convenes to debate the next move. One devil, Moloch, makes the case for an all-out war against God and Heaven, arguing that they have nothing to lose because they are already in Hell. Another devil, Belial, disagrees, suggesting that they do nothing. He believes that God may eventually become less angry and dispense with their suffering. Mammon, a third devil, says that trying to return to Heaven would be useless. He suggests that they make Hell a domain that would be comparable to Heaven. Finally Beelzebub, Satan's second-in-command, suggests that the devils find God's new world and either conquer it for themselves or corrupt its inhabitants, mankind. The idea is actually Satan's, but he has Beelzebub suggest it so that he can volunteer and look heroic to the other devils. The council agrees and decides to use God's new creation, man, as a tool in their war. Satan sets out to find the new world where man resides. He flies out of the Gates of Hell with the help of his children, Death and Sin.
On the other side of the Gates of Hell are Chaos and Night, the "dark materials" that God uses to create worlds. They give him directions to Earth after Satan promises to turn the universe back over to them to control. Satan approaches Earth with God watching him all the while. Even though God has ordained that man has free will, he knows that Satan will succeed in corrupting man. God warns that although man can be saved, he must accept that death is a just punishment for his sins.
Milton continues his allusions to Satan as a military commander when he shows the council of devils debating strategies to defeat God. Though they seem to have an orderly debate, none realize that Satan has already decided what will be done: he is letting them believe they have some kind of say in the matter. It's possible that Milton is satirizing what he saw as the corruptness and ineffectualness of politics here—that under the illusion of orderly proceedings and polite discussion, puppet strings are secretly being pulled by those in power. Satan is also compared to a Persian or Indian ruler in an implicit criticism of monarchy; because God is the only true king, Satan's rich throne indicates the empty, corrupt splendor of all earthly kings.
By focusing on the complaints of the devils, Milton continues to portray them as sympathetic; they are forced to do God's bidding without any say in the matter and without really understanding that God knows and controls the outcome of everything. This relates to the epic's overall theme of fate and free will, since Satan believes that God restricts his ability to be free. Yet Satan does not seem to question why, if God rules every action and has prior knowledge, he would be "allowed" to leave Hell and fly to Earth to corrupt God's new creation.
Sin, Death, Chaos, and Night are all literal characters in Paradise Lost as well as allegories—they represent a larger concept. Through the characters of Sin and Death, Milton seems to be suggesting that sin and death arise from disobeying God's wishes. Satan creates Sin from his mind after becoming jealous of the Son, and so Sin becomes both an idea and a character. By colluding with Satan, Death and Chaos help bring the concepts of sin and death into the earthly world.
Milton again invokes his heavenly muse at the beginning of Book 3. He asks for her guidance in helping him to describe God and Heaven and compares himself to the blind Greek epic poet Homer and the blind prophets Phineas and Tiresias. Book 3 shifts from the newly erected Pandemonium in Hell to God's court in Heaven. God watches as Satan approaches Earth and calls together his heavenly council. God is all-seeing and all-knowing, so he knows that man will ultimately be corrupted by Satan. However, since God imbued man with the free will required to resist Satan's temptation, man's downfall will be his own fault. Though God already knows the past, present, and future outcome of all things, he says that nothing is predestined; knowing what happens does not mean that he controls it. God decides that he will ultimately offer man the chance for redemption but that somebody will have to die in his place for the sins he commits. The Son offers himself as a sacrifice for man's sins in order to balance the scales of divine justice. God is pleased to hear this and says that even though humanity will suffer because of man's choices, humans will also be redeemed through the Son's act of sacrifice.
Satan arrives at the borders of Earth and encounters a staircase to Heaven. There he encounters the angel Uriel and quickly disguises himself as an angel. He tells Uriel that he has come down from Heaven to see the new world God has created. Uriel gives the disguised Satan directions to enter Paradise, where man resides.
Milton's religious beliefs led him to reject the Christian belief of predestination: the notion that God had already predestined all of man's actions. Milton believed that even though God could see the past, present, and future, he endowed humans with the free will to make their own choices inside of that foreknowledge. Milton's God argues that if he did not endow humankind with free will, then they would be unable to choose to be obedient to him and therefore would not truly love or worship him of their own free will. Essentially, God says that knowing what man will do does not mean that he is the cause of man's actions. For readers of Paradise Lost, these distinctions seem tricky and even contradictory, since it is difficult to conceptualize that God knows the future, including his own actions, and yet is not responsible for future events.
Although God has not preordained the fall of man, he still knows that it will happen, and so he can plan to create good out of Satan's evil plans. Even though we see God and Satan in the same section here, the contrast of the passiveness of God and the determination of Satan continues to pit Satan as the unlikely protagonist of the story.
Conceptualizing the unique characters of God and the Son is difficult. It might be easier to imagine God as pure spirit and the Son as a more material form who can carry out God's plans. To complicate things further, the Son is also considered to be Jesus, who is a separate figure from God. Milton treats God and the Son as separate characters, rather than as the same entity.
Now that Satan has gained entrance to Paradise, he stands on a nearby mountain and views it for the first time. He has a moment of doubt as he beholds its beauty and pristine landscape. He thinks about his relationship with God, who had only shown him kindness and fairness until he rebelled. He laments the fact that God had made him a powerful angel in Heaven, because it gave him the yearning for more power. Satan considers repenting to God but still feels too bitter over everything that has transpired for it to be an honest confession. He also realizes that because he lives separated from God and thus in despair, he is unable to escape Hell even in this new Paradise. Hell is in his mind.
Newly determined, Satan recommits to his plan to corrupt man and overthrow good with evil. Satan enters Paradise and disguises himself as a bird, roosting in a tree in the Garden of Eden. From his perch he notices two beings that look different from all the other animals in the Garden. He watches them eat and drink and is filled with envy and rage. Satan experiences another pang of guilt as he contemplates what he is about to do to these two humans, but his resolution to corrupt them remains. He leaves the tree and approaches them.
The story shifts to Adam and Eve, who are discussing how blessed they feel to be in the Garden and how they must remain obedient to God's order that they not eat any fruit from the Tree of Knowledge. Adam and Eve have no concept of death, but they agree that it must be bad and they know they will suffer it if they disobey God. Eve recalls how she first met Adam and the story of her earliest understanding of being alive. She describes encountering her reflection in a pond without realizing she is seeing herself. She remembers initially turning away from Adam when she met him because she found herself more beautiful. As Satan eavesdrops on them, he is filled with jealousy at their happiness. He decides to use the Tree of Knowledge as the tool of his corruption because God has forbidden it.
Uriel has been watching the disguised Satan from afar and realizes that he has been fooled. He tells one of the guardian archangels of Eden, Gabriel, that he suspects a fallen angel has entered Paradise. Gabriel sends two angels to search for the being that Uriel described, and they find Satan disguised as a toad. They force him to shape-shift back into his true form, and they bring him to Gabriel, who recognizes him as Satan. Gabriel questions him, and Satan tries to lie about his motives. Gabriel sees through him and tells Satan he will bring him back to Hell and seal the gates so he can never leave. They prepare to battle each other, but God puts a stop to it, sending up a pair of Golden Scales in the sky. The scales show that if Satan tries to fight, he will be defeated. Convinced that he would be on the losing end of a battle, Satan leaves for Hell.
Because Satan ultimately refuses to repent to God, all that is left for him is suffering and Hell; he remains determined to spread that suffering to God's new world. Even though Satan is moved by the beauty of Paradise and the innocence of Adam and Eve, seeing what he can no longer attain moves him to recommit to his plan of corruption. Milton again shows Satan as a somewhat sympathetic character, afflicted by envy and doubt. It's no coincidence that this is also the first time that the reader has access to Satan's internal thoughts, which conflict with his outward displays of confidence and hubris. The idea that Hell can exist in Satan's mind as well as being an actual place is an important concept; after Adam and Eve are told that they must leave Paradise, the archangel Michael assures them that Paradise is not just a physical location, but a state of mind that they can find within themselves.
The Tree of Knowledge and God's command that Adam and Eve not eat from it suggests the connection between ignorance and innocence. Adam and Eve are so ignorant that they don't even understand the concept of their punishment: death.
Eve's story of coming into existence and learning about her origin reflects the prevailing beliefs about women during Milton's time that women were inferior to men. Milton portrays Eve as vain when she gets caught up in her own reflection and is unable to recognize Adam's superiority when she first sees him. Milton argues that Adam is in communication with God while Eve primarily experiences God indirectly through her love of Adam. In Satan's eyes this makes Eve the easier target of his temptation. However, it is important that Milton explicitly says that Adam and Eve, as a married couple, have a physical relationship and that there is nothing implicitly evil or corrupt about sex.
God's interference in the conflict between Satan and Gabriel shows what power he has over everything—a power that Satan recognizes—causing him to flee rather than stay and battle Gabriel.
After Adam and Eve wake up the next morning, Eve recalls a dream she has had in which an angel told her to eat from the Tree of Knowledge. She explains the dream to Adam: In the dream, the angel offers her a piece of fruit and she hesitates. The angel tells her that if she eats the fruit she will become godlike. Eve says she awoke before she could eat the fruit. After Eve relates the dream, Adam reassures her that she did nothing wrong and that she has remained obedient to God.
God watches Adam and Eve from Heaven and sighs to the archangel Raphael that he knows they will ultimately give in to their temptation to eat the fruit. He sends Raphael to visit them in Eden, where Raphael reminds them that they must obey God even though free will gives them the choice to disobey him. Raphael tells Adam and Eve about Satan's rebellion in Heaven, which began with Satan's jealousy toward the Son, who would become King of the Angels. In preparation to fight God, Satan gathered all the angels under his command and attempted to trick them into following him away from the rule of God and the Son. They all agreed to follow Satan except for Abdiel, who tried to convince them to repent and remain in Heaven. They mocked him, and Abdiel alone returned to God.
Adam and Eve are right to be troubled by Eve's dream, for it's unlikely that she would have come up with the idea of disobeying God on her own. But Eve has committed no sin; the temptation came from Satan, not her own inclination. Yet the dream is still a foreshadowing and plants a seed of uneasiness in both Adam and Eve, though the reader already knows how it will end. In this way the reader has the same vantage point as God, able to see the future outcome as well as past actions that will result in their disobedience. And as much as either God or the reader would like to prevent disobedience, free will dictates that only Adam and Eve could have prevented it.
Raphael's meeting with Adam and Eve heightens the inevitable tragedy that will befall them, since Raphael is there to explain that they have free will and so any choice to give in to temptation will be their error. It is ironic that Raphael is sent to provide them with knowledge about their own ignorance, which should help them resist temptation. In the end, the irony is evident in that Adam and Eve know what will happen if they give in to temptation but do it anyway.
There's a political parallel between Satan's rebellion in Heaven against what he sees as God's tyranny and Milton's view of the English monarchy as a tyrannical power. Yet Milton uses the angel Abdiel as the lone voice justifying the ways of God and, as such, seems to be suggesting that God's rule is rightful and just.
Raphael continues to tell Adam the story of Satan's rebellion in Heaven. Raphael says that after the rebellion, Abdiel returned to God and the other angels who did not follow Satan and that God praised him for his loyalty. Then God put together his own army of angels, though he is careful to ensure that it does not outnumber Satan's army of rebels. The battle between the armies began, and the rebels were ultimately forced into Hell by the Son.
Raphael tells Adam that the loss of the battle by Satan means that Satan now wants to corrupt man, since man is God's newest and most prized creation. He warns Adam not to give in to temptation, since that would be to disobey God.
Although Milton is critical of other epic poets for only writing stories about war, Milton lines up Paradise Lost yet again with the ancient Greek epics, depicting armies in deep battle with gains and losses on both sides. The difference here is that angels cannot be killed, only wounded, and therefore the battle could go on forever. God is even able to stop the battle when he decides it has gone on long enough—and he never even gets involved, otherwise. Satan and the other rebel angels never seem to realize how futile their battle ultimately is, given God's omnipotence.
It's possible that something is lost in Raphael's "translation" of Heaven to Adam. He explains to Adam that he can only describe Heaven in metaphors that Adam might understand. Otherwise Adam wouldn't be able to grasp the concept of Heaven. This explains why he describes "arming" battalions of immortal angels, an idea that seems somewhat silly given that they can't actually die. This serves to make the battle seem almost boring to the modern reader, who knows that nothing terrible or dramatic will befall any of the angels, since they can heal almost instantly. Similarly, Satan's belief that a cannon could destroy God's angels seems ridiculous—they are still immortal.
Raphael's larger point to Adam seems to be that even though Satan and the other fallen angels rebelled, they were never an actual threat to God or Heaven. Raphael wants Adam to see that even if disobeying God feels like a powerful choice, power is only an illusion. God can do what he wants whenever he wants.