The epic poem Paradise Lost by John Milton tells of the casting out of paradise of Satan and other rebellious angels. Satan and his demons devise a plan to retaliate against God by corrupting his new creation—Man. Since Adam and Eve have been given free will, God allows Satan to approach and tempt them. Adam and Eve disobey God and fall from grace, and God sends the archangel Michael to drive them out of the Garden of Eden.

In the prologue to book 1, Milton delineates two main themes of Paradise Lost. In line 1, he announces that he will write "of man's first disobedience." That obedience to God is an absolute requirement of all creation is emphasized throughout the poem. The expulsion of Satan and his minions from heaven is an example of the consequences of disobedience and rebellion. Similarly, the punishment of Adam and Eve for their disobedience is expulsion from the Garden of Eden.

The hierarchy of God's authority over his creation must be observed at all times, and to disregard God's supremacy has drastic ramifications. Furthermore, as Milton explains, Adam and Eve's transgression brings "death into the world and all our woe." Note that the use of the word "our" makes it clear that man's first disobedience condemns the entire human race to death and expulsion from the heavenly garden.

Milton proclaims the other main theme of the poem in lines 24 to 26: "That to the height of this great argument I may assert Eternal Providence and justify the ways of God to men." According to the Merriam-Webster Dictionary, providence means "divine guidance and care," or, "God conceived as the power sustaining and guiding human destiny." To justify something is "to prove or show to be just, right, or reasonable."

In other words, Milton's intention is not only to tell of man's disobedience and fall but also to prove that God's actions as a result are just, right, and reasonable considering the circumstances. It is important to remember that in books 11 and 12 of Paradise Lost, before he sends Adam and Eve out of the garden, Michael gives them an overview of Biblical history, including an account of the Messiah and his ultimate victory over death.

The main theme of Paradise Lost is announced in the very first line: man's first disobedience. It was this defiance of God's express commands that first introduced sin into the world, an inheritance with which humankind has had to live with ever since.

Adam and Eve's act of transgression—eating the forbidden fruit of the Tree of Knowledge—also allowed Satan to gain a foothold in God's previously serene and peaceful creation. Satan's own act of disobedience against the Almighty caused him to be cast down from Heaven as a fallen angel. Realizing that a full-frontal assault on God and his angels would be counter-productive, Satan hit upon the diabolical idea of introducing evil into the world.

He achieves his dastardly aims through corrupting Eve, tempting her with the fruit of the Tree of Knowledge. Eve's act of disobedience has serious consequences, both for herself and Adam. Once Adam has also tasted the forbidden fruit, he too is damned, condemned to accompany Eve in her exile from Paradise.

According to orthodox Christianity the long-term consequences of man's first disobedience have been no less disastrous, with humankind having to deal with sin, evil, and death. At the same time, Adam and Eve's transgression can be seen as precipitating a so-called "Fortunate Fall," in that if they hadn't brought sin into the world, there wouldn't have been a need for God to send his only begotten son, Jesus Christ, to save us.

The main theme of Paradise Lost by poet John Milton is the rejection of God’s Laws.

This epic work deals with Satan’s rejection of God’s Law and Satan’s subsequent expulsion to earth where he seeks to ruin Man. Satan is expelled with a third of the angels (now demons) who chose to follow him rather than the God.

Satan then tempts Eve to sin and by extension Adam as well. The result is a fallen world that has made a conscious decision to follow their own way and not the way God had in mind from the beginning. Paradise Lost deals with Satan’s attempt to influence Man. It also deals with the loss of Paradise by Mankind because of the original sin of Adam and Eve.

The main point to consider when reading Paradise Lost is that Satan and Man were given everything beautiful and wonderful from God. They were also given “free moral choice.” God set before Satan, and then later Mankind (Adam and Eve), the freedom to choose a way that leads to life, or a way that may seem attractive and right – but leads to Death. Satan beguiled Eve, which led to Adam’s downfall as well.

The rejection of God’s Law resulted in Satan (and the fallen angels) being thrown out of Heaven to the Earth, and Adam and Eve being thrown out of Eden. Therefore, the rejection of God and His Laws set in motion universe-changing events and also the ages long battle between good and evil.