How do we know the Book of Revelation is about encouragement?

The central theme of Revelation revolves around the encouragement it provides to believers enduring hardship. John was tasked by Christ to write this letter to offer hope amidst the despair faced by early Christians. Rather than being a text of fear, Revelation assures believers of the certainty of Christ's reign and the ultimate judgment of evil. The imagery used throughout the letter helps portray the cosmic battle between good and evil and assures the faithful that they are on the winning side. By understanding this epistle's purpose, we can appreciate its role as a source of comfort and strength for Christians facing various trials.