According to the Bible, and a religious song you may know, Joshua fought a battle at Jericho. The one-time spook and former assistant to Moses led the Israelites around the city walls on successive days until, after seven circuits on the seventh day, the walls fell down. Then the Israelites, following divine commands, slaughtered every living thing in the city—adults, children, and their pets. It’s not a happy story so you should breathe a sigh of relief that these events never took place. When archaeologists excavated the site at Tell es-Sultan, where the battle was supposed to have taken place, they discovered that it had been abandoned long before Joshua’s arrival.
Studying the Bible’s historical accuracy is always fraught. Our main sources are ancient texts that have been edited by many hands, were copied dozens of times over, and were written with an eye to the theological message rather than the facts. For centuries, therefore, scholars have used archaeological methods to supplement our knowledge and test the Bible’s accuracy. Even then, the results are controversial and difficult to interpret. A new study methodology using magnetic data may change some of that.
Tel Aviv University doctoral student Yoav Vaknin is the lead author of a pioneering a new study of biblical archaeology that applies archaeomagnetic technologies to date the military campaigns described in the Bible. The article, which was recently published in the open access journal PNAS, assembles an array of data drawn from studies of 17 different archaeological sites to build a timeline of ancient destruction. The geomagnetic dataset he compiled includes evidence of 21 layers of destruction. It is, as Vittoria Benzine observed, a “geological ledger of conquests by Aramean, Assyrian, and Babylonian armies against the Kingdoms of Israel and Judah.”
Unlike more conventional archaeological methods like stratigraphy (which looks at different strata in the soil), archaeomagnetic dating is interested in the magnetic field generated by the Earth’s core. It examines the layer of liquid iron in the planet’s outer core. Ron Shaar, who led the development of the methodology itself, said that “Until recently scientists believed that the [Earth’s core] remains stable for decades, but archaeomagnetic research has contradicted this assumption by revealing some extreme and unpredictable changes in antiquity.”
Vaknin explained that archaeological material contains magnetic minerals. “On the atomic level, one can imagine the magnetic signal of these minerals as a tiny needle of a compass.” When, say, a clay brick is incinerated during the sack of a city the brick preserves the magnetic signal at the moment the city caught fire. If geophysicists know the magnetic states of various eras at certain periods in time, then they can determine origin of the materials.
The study focuses on items made of mud (mostly bricks but also loom weights and beehives crafted from clay) that were burned during period of military unrest and invasion. His findings confirm some biblical stories and archaeological theories, and debunk others.
Tel Beth-Shean, in the northern district of modern Israel, was previously thought by archaeologists to have been destroyed by the Aramean king Hazael in 830 BCE. Vaknin and his co-authors suggest that it was actually sacked between 70 (95 percent probability) and 100 (68 percent probability) years earlier. This would mean, argues Vaknin, that the city was most likely destroyed during a military campaign by Pharaoh Shoshenq I. This campaign is mentioned in both the Hebrew Bible (2 Kings 14:25026) and in a relief of the campaign carved into the walls of the Temple of Karnak in Egypt.
Most surprisingly, Vaknin’s findings suggest that the Babylonians were not responsible for the total destruction of Judah in 586 B.C. (2 Kings 24:18; Jeremiah 1:3; 39:2; 52:5-6). The intensity results from sites in the Negev, southern Judean mountains, and southern Judean foothills, however, suggest that towns in this region survived the Babylonian invasion. It was only several decades later, after Jerusalem and its environs had been destroyed, that others (most likely the Edomites) attacked these smaller settlements. The discovery may help explain some of the animosity towards the Edomites that we find in the Hebrew Bible.
It's undeniable that archaeomagnetic dating offers another complementary method for establishing the chronology of these events. Much like carbon dating (which works from a sample set of data), it is able to use the larger data sets gathered from the numerous archaeological studies in the region to date military campaigns with greater precision. It’s promising and exciting work.
At the same time, some of the media buzz around the findings may overestimate the significance of the method and overlook some of its limits. Though you would not know it from some of the reporting, archaeology is already a highly technological savvy discipline that utilizes an array of technologies (like, for example, carbon 14 dating) to develop hypotheses and reach conclusions. As with carbon dating, archaeomagnetic findings are expressed as percentages not binaries, but this does not show up in news reports. You can forgive the transformation of a 95 percent probability into a certainty, but 68 percent probability is less decisive. Let’s be frank, it’s a C+. This isn’t Vaknin’s fault; it’s just what happens when archaeology makes news.
It's also important to note that the findings only express the facts of a site’s destruction, not its cause. As Dr. Laura Zucconi, a professor of history and archaeology at Stockton University who has written on copper mines and the Edomites, told me, “It’s a very interesting new dating method,” but it doesn’t tell us why a site was destroyed. “If a site has a destruction layer but lacks other information, we have no way of knowing if it was warfare or simply an earthquake with resulting fire.” While we do have other methods for dating sites, says Zucconi, multiple methods of analysis are always preferable. “Even if [archaeomagnetic analysis] replicates other methods, it’s good to have different approaches because the material” used in one methodology may not always be available. Because of a phenomenon known as the Hallstatt plateau, for example, carbon 14 dating methods are unhelpful for dating materials from between 800-400 B.C.. Having another instrument in the archaeological toolbox is important.
Vaknin told Artnet news that he hopes to establish a similar chronological leger for the most controversial period of ancient Levantine archaeology: 1300-900 B.C.. This is, according to the Bible, the period during which the Exodus took place, Israelites settled in the land of Canaan, and David was king. This is a fiercely debated time period the events of which have political ramifications in the present. It will take him out of the proverbial frying and into the proverbial fire. But after five years studying the effects of incineration on clay bricks, and with a well-stocked arsenal of archaeological tools, he is well suited for the challenge.