The story of Margaret, a 3rd-century saint, was popularized in the 13th century Golden Legend, a collection of hagiographies or saints’ stories. Margaret was imprisioned and tortured because she refused to renounce her Christian faith. While in prison Satan, disguised as dragon, swallowed Margaret. But her holiness, or a cross she carried with her, (depending on which version of the story is consulted) irritated the stomach of the dragon and she was ejected unharmed.
“And whilst she was in prison, she prayed our Lord that the fiend that had fought with her, he would visibly show him unto her. And then appeared a horrible dragon and assailed her, and would have devoured her, but she made the sign of the cross, and anon he vanished away. And in another place it is said that he swallowed her into his belly, she making the sign of the cross. And the belly brake asunder, and so she issued out all whole and sound. This swallowing and breaking of the belly of the dragon is said that it is apocryphal.” The Golden Legend, Vol. IV. Compiled by Jacobus de Voragine, Archbishop of Genoa, 1275 First Edition Published 1470. English by William Caston, 1483
A more recent translation from Latin is as follows:
Margaret was taken down and put back in jail, where a marvelous light shone around her. There she prayed the Lord to let her see the enemy who was fighting her, and a hideous dragon appeared, but when the beast came at her to devour her, she made the sign of the cross and it vanished. Or, as we read elsewhere, the dragon opened its maw over her head, put out its tongue under her feet, and swallowed her in one gulp. But when it was trying to digest her, she shielded herself with the sign of the cross, and by the power of the cross the dragon burst open and the virgin emerged unscathed. What is said here, however, about the beast swallowing the maiden and bursting asunder is considered apocryphal and not to be taken seriously.”
Ryan, William Granger, and Eamon Duffy. “Saint Margaret.” In The Golden Legend: Readings on the Saints, 368-70. Princeton University Press, 2012. www.jstor.org/stable/j.ctt7stkm.98.
To learn more about the history of dragons, see The Evil, Medieval Ancestors of Modern Dragons
Image: 15th century French Book of Hours; Courtesy of the British Library Catalogue of Illuminated Manuscripts.