DE MONARCHIA OF DANTE ALIGHIERI
CHAPTER XIII: Christ in dying confirmed the jurisdiction of the Roman Empire over all humanity.
1. And if the Roman Empire did not exist by Right, the sin of Adam was not punished in Christ. This, however, is false; so the contradictory from which it follows is true. The falsity of the consequent is apparent in this. By the sin of Adam we are all sinners, according to the Apostle: "As by one man sin entered into the world, and death by sin, so death passed upon all men, for that all have sinned.'" If satisfaction had not been given for this sin through the death of Christ, we, owing to our depraved nature, should still be children of wrath. But this is not so, for the Apostle speaks in Ephesians of the Father "having predestined us unto the adoption of children by Jesus Christ to Himself according to the good pleasure of His will, to the praise of the glory of His grace, wherein He hath made us accepted in the beloved, in whom we have redemption by His blood, the forgiveness of sins according to the riches of His grace, wherein He has abounded toward us."  And Christ Himself, suffering in Himself the punishment, says in John, "It is finished."  And when a thing is finished, nothing remains to be done.
2. For greater clearness, let it be understood that punishment is not simply penalty visited upon the doer of wrong, but penalty visited upon the doer of wrong by one having penal jurisdiction. Wherefore unless punishment is inflicted by a lawful judge, it is no punishment; rather must it be called a wrong. Hence the man of the Hebrews said to Moses, "Who made thee a judge over us?" 
3. If therefore Christ did not suffer under a lawful judge,  his penalty was not punishment. Lawful judge meant in that case one having jurisdiction over the entire human race, since all humanity was punished in the flesh of Christ, who, as the Prophet says, "hath borne our griefs and carried our sorrows."  And Tiberius Caesar, whose vicar was Pilate, would not have possessed jurisdiction over the entire human race had not the Roman Empire existed by Right. Herod, albeit as ignorant of what he did as Caiaphas  of what truth he spake concerning the heavenly decree, for this reason sent Christ to be judged by Pilate, as Luke  writes in his Gospel. For Herod was not an official of Tiberius under the ensign of the eagle or the Senate, but a king appointed by him to a particular kingdom, and governing it under the ensign of the kingdom committed to him. 
4. Wherefore let those who pretend they are sons of the Church cease to defame the Roman Empire, to which Christ the Bridegroom gave His sanction both at the beginning and at the close of His warfare. And now, I believe, it is sufficiently obvious that the Roman people appropriated the Empire of the world by Right.
5. O people, how blessed hadst thou been, O Ausonia how glorious, had he who enfeebled thy sovereignty never been born, or never been deceived by the piety of his purpose! 
1. Rom. 5. 12. In De Mon. 1. 16 Dante dates "all our errors" from the fall of Adam. In Par. 7 Beatrice explains to Dante the nature of human redemption. Cf. 1. 85: "Your nature, when it all sinned in its seed, was removed from these dignities as from Paradise; nor could it recover them, ... by any way without passing through some one of these roads; either that God alone of his clemency should have put away, or that man should have made satisfaction for his folly."
Purg. 32. 37. Here in the vision of the Church and the Empire Dante symbolizes the fall and redemption of man, the errors of avarice in the Church, and the universal jurisdiction of Monarchy. "I heard all murmur 'Adam,' then they circled a plant despoiled of flowers and of leafage too on every branch. Its foliage, which spreads the wider as it is the higher up, would be wondered at for height by the Indians in their forests. 'Blessed art thou, Grifon, that thou tearest not with thy beak of this wood sweet to the taste, since ill was the belly griped therefrom.'" As Plumptre remarks, the apostrophe to the grifon is the thought developed in the second book of De Mon.
2. Eph. 1. 5-8.
3. The work of redeeming the human race is finished. John 19. 30.
4. Exod. 2. 14.
5. "Sub ordine judice."
6. Is. 53. 4. Quoted Letter 6. 6.
7. John 18. 14: "Now Caiaphas was he which gave counsel to the Jews that it was expedient that one man should die for the people."
8. Luke 23. 11.
9. Pilate was the real Roman regent. Cf. Par. 6. 86, where Tiberius is called "the third Caesar," and read all the canto for Justinian's account of the Roman Empire.
10. That Constantine's purpose was high Dante always insisted on. See De Mon. 2. 12. 1; and 3. 10 and notes. Par. 20. 58: "Now knows he how the ill, deduced from his good work, is not harmful to him, albeit that the world be thereby destroyed."