What is the author's style in Paradise Lost by John Milton?

The standard definition of an epic, or heroic poem, is that it is a "noble story told in noble verse" (Hutson and McCoy, Epics of the Western World, p. 7), a continuous narrative concerning a heroic person from history or tradition. The epic uses historical and mythological material to exemplify a truth which is greater than both. The subject of an epic poem is to be a story which both delights and instructs, embodying the cultural and moral ideals of its time but with universal implications.

Milton chooses an unusual subject for his great epic poem, ostensibly shunning "Wars, hitherto the only Argument / Heroic deem'd" (IX.28-9), in favor of the sad task of relating an "argument / Not less but more Heroic than the wrath / Of Stern Achilles on his Foe pursu'd / Thrice Fugitive about Troy Wall" (DC. 13-15). The "higher argument" which Milton chooses is the story of the Creation, Fall, and Redemption of humankind, combining the epic conventions of high moral purpose with the conviction that in presenting a Biblical theme, he is also representing a higher truth. The fate of humankind thus becomes the unifying force of the poem, as Milton presents the ideals of private virtue and public rectitude by exploring both the nobility and weakness of fallen humanity.