The inscription in Hezekiah's tunnel was left by the diggers, not the king

Under the oldest part of Jerusalem runs a tunnel about 1,750 feet long, cut through solid rock to carry water from the Gihon Spring to a pool inside the city. In 1880 a boy wading near its southern end noticed letters carved into the wall. They turned out to be six lines of Hebrew in the old script of the kings' era, one of the longest Hebrew inscriptions of that period ever found.

It does not praise a king or a god. It describes a moment underground: two crews cutting toward each other from opposite ends, close enough at last to hear each other's voices through the rock. Then, in the inscription's words, "on the day of the breakthrough, the stonecutters struck each toward the other, axe against axe, and the water flowed from the spring to the pool, twelve hundred cubits."

The Bible credits the project to King Hezekiah, around 700 BCE. 2 Kings 20:20 says he "made the pool, and the conduit, and brought water into the city," and 2 Chronicles 32:30 adds that he channeled the Gihon's water inside the walls, a precaution against an Assyrian siege. The inscription's letter shapes fit his era, and a 2003 study dating plaster and mineral deposits in the tunnel pointed to about 700 BCE; a minority of scholars have argued for a later date. The one thing the inscription never does is name Hezekiah. It was carved in the dark, where almost no one would ever read it, by workers marking the day they met in the middle.