THE BEDROCK OF MONOTHEISM: THE GEOLOGY OF JERUSALEM AND ITS HISTORICAL AND RELIGIOUS IMPLICATIONS

In order to sustain stable populations, communities in the ancient world were situated near stable sources of freshwater. By examining the ways in which the geology of Jerusalem has had an effect on its history, it becomes evident that religion can “spring up” around sources of water in a similar fashion. Though historians have suggested several reasons for the choice of Jerusalem as the City of David, including cultural and military concerns; I would infer that the Israelites may have had an extensive familiarity with the sub-surface geology of the area. Situated on a structural saddle between the Judea and Hebron Anticlines, Jerusalem benefits in many ways from its underlying structure and stratigraphy, most noticeably in its water resources: groundwater in the Lower Judea Group brings a steady flow of freshwater to Jerusalem. Located just outside the Old City walls, the Spring of Gihon was the only surficial source of freshwater for a great distance around the city. Although Jerusalem rests on the Mt. Scopus Group, Upper Cretaceous formations which consist primarily of chalk and chert, there is locally exposed Judea Group limestone present as well. Biblical and historical sources suggest that ancient Israelites may have filtered their drinking water through limestone in order to “purify” it, adding to Jerusalem’s appeal.

The relationship between the geology of Jerusalem and the advent of monotheism is a more linear one. When King David was first attempting to seize the city from the Jebusites in 1000 BCE, the city’s defenders sealed themselves up in its citadel. In order to gain entry, David’s elite guard dug a tunnel which took advantage of a solution feature in the local bedrock. This gave them access to the citadel’s well that intersected the spring, and they opened the gates from the inside. The Spring of Gihon and the subsurface stratigraphy would be featured in other battles for Jerusalem. When the Assyrian war machine approached the city in 701 BCE, King Hezekiah had a tunnel dug which diverted the subsurface flow of the spring to more secure wells. This played a pivotal role in making Jerusalem the only city in history to have survived an Assyrian siege. These battles are just two in a series of events which directly influenced the rise of Judean monotheism which has had a global impact on culture and religion 3,000 years later.