The comet represents the uprising of a rebellious power against the supreme and orderly dominion of God.  The angel Abdiel says to Satan: 

             “Fool! not to think how vain
     Against the Omnipotent to rise in arms;
     Who out of smallest things could without end
     Have raised incessant armies to defeat
     Thy folly; or, with solitary hand,
     Reaching beyond all limit, at one blow,
     Unaided, could have finished thee, and whelmed
     Thy legions under darkness.”

The battle begins: 

“Now storming fury rose, And clamor such as heard in heav’n till now Was never; arms on armor clashing brayed {p. 248} Horrible discord, and the madding wheels Of brazen chariots raged; dire was the noise Of conflict; overhead the dismal hiss Of fiery darts in flaming volleys flew, And, flying, vaulted either host with fire. . . .  Army ’gainst army, numberless to raise Dreadful combustion warring and disturb Though not destroy, their happy native seat.
        . . .  Sometimes on firm ground
A standing fight, then soaring on main wing Tormented all the air, all air seemed then Conflicting fire.”

Michael, the archangel, denounces Satan as an unknown being a stranger: 

“Author of evil, unknown till thy revolt, Unnamed in heaven . . . how hast thou disturbed Heav’n’s blessed peace, and into nature brought Misery, uncreated till the crime Of thy rebellion! . . .  But think not here To trouble holy rest; heav’n casts thee out From all her confines:  heav’n, the seat of bliss, Brooks not the works of violence and war.  Hence then, and evil go with thee along, Thy offspring, to the place of evil, bell, Thou and thy wicked crew! "

But the comet (Satan) replies that it desires liberty to go where it pleases; it refuses to submit its destructive and erratic course to the domination of the Supreme Good; it proposes—­

             “Here, however, to dwell free
     If not to reign.”

The result, of the first day’s struggle is a drawn battle.

The evil angels meet in a night conference, and prepare gunpowder and cannon, with which to overthrow God’s armies!

“Hollow engines, long and round,
Thick rammed, at th’ other bore with touch of fire {p. 249}
Dilated and infuriate, shall send forth
From far, with thund’ring noise, among our foes
Such implements of mischief, as shall dash
To pieces, and overwhelm whatever stands
Adverse.”

Thus armed, the evil ones renew the fight.  They fire their cannon: 

             “For sudden all at once their reeds
     Put forth, and to a narrow vent applied
     With nicest touch.  Immediate in a flame,
     But soon obscured with clouds, all heav’n appeared,
     From these deep-throated engines belched, whose roar
     Emboweled with outrageous noise the air,
     And all her entrails tore, disgorging foul
     Their devilish glut, chained thunder-bolts and hail
     Of iron globes.”