Religious belief and modern skepticism have been butting heads since the Enlightenment. Here's a case in, um, point: Is the ancient spear in the Imperial Treasury at Vienna's Hofburg Palace really the one that a Roman centurion used to pierce the side of the crucified Jesus Christ? Legend insists that it is, but science is doing its best to fact-check the story. Like the 51-cm relic itself first mentioned in the Gospel of John the tale of the Holy Lance, or Spear of Destiny, has been embellished over the ages. As one oft-quoted account has it: "Whomsoever claims this spear and solves its secrets holds the destiny of the world in his hands, for good or evil."
British metallurgist Robert Feather has decoded some of its secrets. He addressed old beliefs with 21st century X-ray diffraction and fluorescence tests to reveal structure and composition, swab checks for organic material (like blood), and other noninvasive procedures and found the main body of the spear to be medieval, dating to the 7th century at the earliest. Charlemagne may well have possessed the spear in 800 and Hitler's Nazis took it from Vienna in 1938 but Constantine the Great could not have called upon the reputed powers of a weapon that didn't exist to help him Christianize the Roman Empire in the 4th century.
But the story (told in a documentary, The Spear of Christ, which airs in the U.K. this week) does not end there. An iron pin long claimed to be a nail from the crucifixion, hammered into the blade and set off by tiny brass crosses is "con-sistent" in length and shape with a 1st century Roman nail, says Feather. While science can't date the iron fragments around it, he adds, the crosses are significant: someone used them to mark an area believed to contain parts of a nail used in the True Cross. "We're in the realm of speculation," he concedes, "but you cannot rule it out. Some people had faith in it, and faith is a wondrous thing." This mystery may well be eternal.