Prophecy, in a broad sense, is the prediction of future events. The etymology of the word is Greek, from pro- "before" plus the root of phanai "speak", i. e. "speaking before" or "foretelling" (proclamation). Prophecy is a general term for assertions presented as the revelation of divine will. Sometimes the Greek word mantik (divination) is translated as prophecy.

Throughout history, people have sought knowledge of future events from special individuals or groups who were thought to have the gift of prophecy, such as Oracles at Delphi in ancient Greece. Cultures in which prophecy played an important role include the North American Indians, Mayans, Celts, Druids, Chinese, Chaldeans, Assyrians, Egyptians, Hindus, Hebrews, Tibetans, Greeks, and many in the Christian tradition, among others.

Throughout the history of the Prayer Vigil for the Earth, various participants have presented the prophecies of their peoples. Many of these prophecies are ancient and have a great bearing on the events of today.