Eschatology ⁱ/ˌɛskəˈtɒlədʒi/ (from the Greek ἔσχατος/ἐσχάτη/ἔσχατον, eschatos/eschatē/eschaton meaning "last" and -logy meaning "the study of", first used in English around 1550) is a part of theology, philosophy, and futurology concerned with what are believed to be the final events of history, the ultimate destiny of humanity—commonly referred to as the end of the world or the "World to Come."

The Oxford English Dictionary defines eschatology as "The department of theological science concerned with ‘the four last things: death, judgement, heaven, and hell’."

In the context of mysticism, the phrase refers metaphorically to the end of ordinary reality and reunion with the Divine. In many religions it is taught as an existing future event prophesied in sacred texts or folklore. More broadly, eschatology may encompass related concepts such as the Messiah or Messianic Age, the end time, and the end of days.

Gog and Magog (Hebrew: גּוֹג וּמָגוֹג‎‎ Gog u-Magog; Arabic: يَأْجُوج وَمَأْجُوج‎ Yaʾjūj wa-Maʾjūj) are names that appear primarily in various Jewish, Christian and Muslim scriptures, as well as numerous subsequent references in other works. Their context can be either genealogical (as Magog in Genesis 10:2) or eschatological and apocalyptic, as in Ezekiel and Revelation. They are sometimes individuals, sometimes peoples, and sometimes geographic regions. The passages from Ezekiel and Revelation in particular have attracted attention due to their prophetic descriptions of conflicts said to occur near the "End times".

The etymology of both the names Gog and Magog remains uncertain. The ma- at the beginning of Magog may indicate a land, or it may mean "from", so that Magog means "of the land of Gog" or "from Gog". Gog may originate as the Hebrew version of the name of Gyges of Lydia, who made his kingdom a great power in the early 7th century BC, but this explanation, although common, is not universally accepted. A different theory is that "Magog" might be a reference to Babylon, by turning BBL ("Babylon" in Hebrew script, which originally had no vowel-signs) into MGG (Magog), but this account, like the others, has problems.