Apr 10, 6:38 PM EDT BOSTON (AP) -- New scientific tests suggest a fragment of papyrus in which Jesus speaks of "my wife" is more likely an ancient document than a forgery, according to an article published Thursday by the Harvard Theological Review. The text, which is written in Coptic and is roughly the size of a business card, specifically contains the phrase "Jesus said to them, my wife." Karen King, a Harvard professor of divinity, says the papyrus probably dates to eighth century Egypt, based on radiocarbon dating and tests on the ink's chemical composition. "If it was written in the eighth or even the ninth century, it's still an ancient document," she said in a conference call Thursday. "It's not a modern forgery." But, she stressed, the fragment doesn't prove that the historical Jesus was actually married. Most reliable evidence from early Christianity is silent on Jesus' marital status, King added. If anything, she says, the papyrus provides insight into early Christianity's debates over family life. "Early Christians were extremely interested in whether or not they should marry or be celibate or whether it was OK to have a family or whether one should remain virginal," King said. King said the papyrus, which contains about eight partial lines of text, appears to make the case that mothers and wives can be disciples. Jesus references his mother, wife, and another female as his disciples apparently discuss whether a woman - identified as "Mary" - can join their ranks. According to King's translation, the text then reads "Jesus said to them, "My wife ..." That is followed in the next line by "... she is able to be my disciple ..." King originally revealed existence of the papyrus in 2012. Calling it the "Gospel of Jesus's Wife," her announcement sparked debate among religious and ancient scholars. But publication of her findings was delayed for the tests. King maintains the "gospel" moniker was appropriate. While the papyrus is too small to discern anything definitive about who composed it, King argued Thursday that the text belongs to a body of ancient texts that illuminate facets of Jesus' life. "It contains a dialogue between Jesus and his disciples," she said. "That would normally put it in the category of gospel." King hopes the research puts to rest questions about the text's authenticity. But Brown University Professor Leo Depuydt, in an analysis also published Thursday by the Harvard Theological Review, was not convinced. He said the text contains grammatical errors that a native Coptic speaker would not make. King suggested in a phone interview that the text is written in an informal style that is found in other ancient Coptic texts. Others have questioned the mysterious provenance of the papyrus. King says she obtained the text in 2011 from a donor that wants to remain anonymous. That owner had purchased the text in 1999 from a collector who, in turn, had acquired it in East Germany around 1963.