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Jerusalem's Hinnom Valley marked the western and southern edges of Jerusalem, beginning along the Western Hill and ending where the Tyropean and Kidron Valleys meet. In the Old Testament, it was often the site where people of Judah sacrificed their children to Baal (2 Kings 23:20; 2 Chron. 28:3,4; Jer. 7:31; 19:5, 6; 32:35).
King Manasseh of Judah added to the negative reputation of the Hinnom Valley by sacrificing some of his own sons in Baal worship there (2 Chron. 33:6). He also practiced sorcery and witchcraft in defiance of God's law. King Josiah, Manasseh's grandson, later destroyed many of these pagan structures and practices. But by that time, Israel was so involved in paganism that God's judgment soon fell upon the people.
Jerusalem's Hinnom Valley also became the perpetual burning-garbage dump and city sewer. Residents sometimes called it the "valley of the sewer" or "the valley of the pagans."
By Jesus' time, the Greek translation of Hinnom Valley, gehenna, became a synonym for hell. Thus the English versions of the Bible translate "Valley of Hinnom" in the New Testament as "hell." With its pagan history and its burning sewer stench, Jerusalem's Hinnom Valley serves as a vivid metaphor for both the Christian and Jewish concept of hell.