Inscriptions dating back to 600 B.C. revealed that much of the Hebrew Bible was written before the demise of the the ancient Kingdom of Judah, further suggesting literacy was more widespread at the time that previously thought.

Led by Tel Aviv University (TAU) Professors Israel Finkelstein and Eliezer Piasetzky, the study helps settle a longstanding debate over whether the first major phase of the Bible was composed before or after the destruction of Judah's capital city, Jerusalem, in 586 B.C.

It is believed that a large group of literate individuals in Judah facilitated the compilation of biblical works that constitute the basis of Judahite history and theology, including the early version of the books of Deuteronomy to Second Kings.

"There's a heated discussion regarding the timing of the composition of a critical mass of biblical texts," said Finkelstein, a professor in TAU's Department of Archaeology and Ancient Near Eastern Civilizations. "But to answer this, one must ask a broader question: What were the literacy rates in Judah at the end of the First Temple period? And what were the literacy rates later on, under Persian rule?"

Using high-tech computerized image processing and machine learning tools, researchers carefully analyzed 16 inscriptions unearthed at an excavation in the remote fort of Arad.

The inscribed ceramic shards - known as ostraca - were written by at least six authors, including correspondence among military officials regarding the movement of troops and provision of wine, oil and flour among the men. This, in turn, shows that reading and writing abilities existed throughout the military chain of command, from the highest echelon all the way down to the deputy quartermaster of the fort.

"We designed an algorithm to distinguish between different authors, then composed a statistical mechanism to assess our findings," explained Barak Sober, one of the study researchers. "Through probability analysis, we eliminated the likelihood that the texts were written by a single author."

Not only do the inscriptions provide evidence of a high literacy rate within Judah's administrative apparatus, but they also provide suitable background for the composition of a critical mass of biblical texts.

"We found indirect evidence of the existence of an educational infrastructure, which could have enabled the composition of biblical texts," said Piasetzky, a professor from TAU's School of Physics and Astronomy. "Literacy existed at all levels of the administrative, military and priestly systems of Judah. Reading and writing were not limited to a tiny elite."

Based on these findings, the first Judahite biblical texts were likely written in Jerusalem by priests and officials in the entourage of the king - possibly King Josiah.

"Now our job is to extrapolate from Arad to a broader area," Finkelstein said. "Adding what we know about Arad to other forts and administrative localities across ancient Judah, we can estimate that many people could read and write during the last phase of the First Temple period. We assume that in a kingdom of some 100,000 people, at least several hundred were literate."

This assumption is based on the idea that if a large number of people could reach the text, it would have been easier to distribute ideas. And since the earliest biblical texts represent the political and theological ideologies of their authors, it only makes sense that a literate group of people could read them.

"Following the fall of Judah, there was a large gap in production of Hebrew inscriptions until the second century B.C., the next period with evidence for widespread literacy," Finkelstein added. "This reduces the odds for a compilation of substantial biblical literature in Jerusalem between ca. 586 and 200 B.C."

Their study was recently published in the journal Proceedings of the National Academy of Sciences.