thumbnail|[[James Tissot, The Tower of Siloam]]
The Tower of Siloam (, ho pyrgos en tō Silōam) was a structure which fell upon 18 people, killing them. Siloam is a neighborhood south of Jerusalem's Old City. In the Gospel of Luke, Jesus refers to the tower's collapse and the death of the 18 in a discourse on the need for individual repentance. The incident is mentioned only once in the New Testament, in Luke 13:4, as part of a section with examples inviting repentance contained in verses 13:1–5.
Biblical reference
thumb|Christ teaching in the Temple
"Some who were present" reported to Jesus that Pontius Pilate had killed some Galileans while they were worshiping. Their example was particularly gruesome since at the moment the Galileans were killed, they were worshiping God by offering sacrifices according to their Jewish religious law.
Apparently those making the report were looking for Jesus to offer some explanation of why bad things happen to normal people—in this case even while they were bringing sacrifices to their God. The "sin and calamity" issue involves a presumption that an extraordinary tragedy in some way must signify extraordinary guilt. It assumes that a victim must have done something terrible for God to allow something so tragic to happen to them.
Jesus responded to the question, answering that the calamities suffered by the victims of the falling of the tower of Siloam were not related to their relative sinfulness. He then diverted the focus onto the interrogators, wanting them to focus on their own souls.</blockquote>
His mention of the fall of the Tower of Siloam added a nuance to his prior point: accidents happen. Therefore, even in the absence of persecution, death can come unexpectedly to anyone, irrespective of how righteous or how sinful they are. He may have been emphasizing that the time granted by God for repentance is limited. where Jesus says, "I give them eternal life, and they shall not perish for ever."
In 1920, Raymond Weill proposed that one of the towers flanking the Pilaster wall next to the Pool of Siloam could be the "Tower of Siloam." In 2023, Nacshon Szanton demonstrated that indeed both towers were constructed in the Hellenistic period, and were rebuilt in the first century.
Other Bible commentators have speculated that the Tower of Siloam may have been part of a Roman aqueduct connected to the Pool of Siloam. At least two aqueducts are known to have carried water to the pool from the Gihon Spring, but these aqueducts were built into the ground, not on elevated viaducts requiring towers.
It has also been speculated that the tower was a fortress built to defend the city, similar to the Phasael tower.
Archaeology
Archaeological excavation has revealed what some Biblical scholars believe to be the ruins of the tower. If so, it is likely the ruins belong to a second tower that was rebuilt after the first tower collapsed. The ruins are a circular foundation approximately 6 metres across.