Eschatology (from the Greek ἔσχατος, “last"), “study of the last things”, is the theological reflection on the final destiny of humanity and of the created world. In the Catholic tradition, the term “Novissimi” (from the Latin novissima, “the last things”) is used to indicate four fundamental aspects of the final destiny of man: Death, Judgement, Hell and Heaven.

In the Old Testament, the allusions to Hell and Heaven are impalpable. In the New Testament, for those who refuse the grace of God Jesus speaks of an exclusion from his Kingdom and of eternal torments (the worm that does not die, the fire that is not quenched, darkness, weeping and gnashing of teeth). 

Later, questions would be asked about this clear dichotomy between Hell and Heaven: what is the destiny of those who are “not perfectly good, though not perfectly evil”? Another possibility gradually emerged: that before entering into Heaven some, or perhaps the majority of individuals must be cleansed by pain: the idea was born of a transitory phase between the two eternal realms of the beatitude of the righteous and the damnation of the wicked, which in the twelfth century would be defined as Purgatory.

When Dante set about writing his poem, the existence of Purgatory had been incorporated in the official doctrine of the Church for around 30 years. Little does it matter that Dante did not strictly follow Catholic doctrine, which would not take the place of divine Judgement by allotting a destiny in the afterlife to specific people. And little does it matter that other Christian churches deny the existence of Purgatory. For as long as we continue to read The Divine Comedy, which stages them, and to contemplate works of art that represent them, the Four Last Things will continue to exist.