Gog and Magog are the prophesied invaders of Israel and the land from which he comes, respectively; or, in the Christian Scriptures (New Testament), evil forces opposed to the people of God. Gog and Magog are said to be decendants of certain Biblical figures, while some dictate them as being a primal race that abandoned their humanity and are the original decendants of Adam the first human.
In ancient times, a colossal wall was built to hold the tribes the Gog and Magog, in order to keep them away. The height and scale of the wall is unknown but it is believed to reach that of mountains. It is made with blocks and sheets of iron, which is strengthened by molten metal and the tribes are unable to cross or scale it.
With a great coalition of forces from throughout the world, the army of Gog will invade Israel “like a cloud covering the earth” and will plunder and loot the cities. Magog will drink all the waters of the Earth, and consume the crops of lands, and plunder cities and villages along with Gog. God, however, will send terrible natural disasters that will destroy Gog and its forces. Gog will be destroyed when God brings forth flaming arrows from the heavens that burn the forces of Gog to a crisp, while Magog will die from sores on their necks and a massive "worm" will emerge and devour them. The defeat of Gog and Magog will demonstrate the power of God and restore good relations between God and his people.
In Revelation, the names Gog and Magog are applied to the evil forces that will join with Satan in the great struggle at the end of time. After Satan has been bound and chained for 1,000 years, he will be released and will rise up against God; he will go forth and deceive the nations of the world, and eventually destroy the wall or barrier that keeps Gog and Magog away from the modern civilization of the world, gathering them together in great numbers to attack the saints and Jerusalem, the city God loves. God will send fire from Heaven to destroy them and will then preside over the Last Judgment.