Charles Ellicott Commentary Luke 13:4

"Or those eighteen, upon whom the tower in Siloam fell, and killed them, think ye that they were offenders above all the men that dwell in Jerusalem?" — Luke 13:4 (ASV)

Upon whom the tower in Siloam fell.—Here, again, we have a reference to an incident not recorded elsewhere. It was clearly one that had impressed the minds of people with horror, as a special judgment. At or near Siloam, the modern Birket-Silwan, is a swimming pool, or tank (John 9:7), where the valley of Tyropœon opens into that of the Kedron.

It was supplied through artificial conduits, and appears to have been one of a series of pools so fed. It is not unlikely, since Siloam was thus connected with the water-system of the city, that the tower in question was part of the works Pilate had planned and partly executed for the construction of an aqueduct. For this project, he appropriated part of the Corban, or sacred treasure of the Temple. If so, the popular excitement which this measure caused (see Note on Matthew 27:2) might well have led people to look on its fall as an instance of a divine judgment on what they regarded as an act of sacrilege.