Bullae are small clay seals — roughly the size of a thumbnail — that were pressed into wet clay to create an impression authenticating a document or container. In the ancient Near East, when a scroll or container was sent from one party to another and needed to be sealed against tampering, the sender would press their personal seal ring or stamp into a small lump of wet clay attached to the string or cord securing the object. The clay would dry and harden, preserving the impression of the seal until the recipient broke it to open the package.
These objects are extraordinarily valuable to archaeologists because they bear identifiable names and titles from specific historical periods, and they're often found in administrative contexts where significant royal or official correspondence originated.
In 2015, in the Ophel — the elevated area between the City of David and the southern wall of the Temple Mount — archaeologist Eilat Mazar's excavation produced two bullae found within inches of each other in the same archaeological stratum.
One reads: "Belonging to Hezekiah, son of Ahaz, king of Judah." It bears the image of a winged sun disc flanked by ankh symbols — royal Egyptian iconography appropriated by Judahite kings during this period. This is a direct physical artifact belonging to the king who built the tunnel.
The second bulla, found within inches of the first, reads: "Belonging to Isaiah the prophet" — with the possible remnant of the word "prophet" in the partially damaged text — and bears the image of a seraph, the winged celestial beings associated specifically with Isaiah's vision in Isaiah 6.
The king who built the tunnel and the prophet who rebuked him, separated by inches in the dirt, united across 2,700 years.