The Catechism in Questions & Answers

549. How do we know about the events of the future?

The doctrine of those things that will come to pass in the future (eschatology) has its basis in Holy Scripture. Many references to the future of salvation history are contained in the gospels and in the letters of the Apostles. Some pivotal statements can also be found in the Revelation of John, which speaks of these future events in figurative language.

Eschatology: see explanation of Question 40.