Several weeks after he had begun to study law, Martin Luther travelled to his parents in Mansfeld. Legend tells that he was surprised by a heavy thunderstorm on the way back, on July 2nd, 1505, at the village of Stotternheim near Erfurt.
Caught in an open field he sought shelter under a tree. A sudden lightning stroke caused him to throw himself down onto the earth. In mortal fear he prayed to St. Anne and vowed: "I will become a monk!". Two weeks later, on July 17th, 1505, Martin Luther entered the Augustinian monastery, the strictest religious community in Erfurt. Neither his friends nor his father were able to make him change his mind.
"Later he told the story as if Heaven had overpowered him", writes Christian Feldmann in "Martin Luther". It is certain that he had already considered becoming a monk and that he possible was afraid of his father's reaction. "A hasty vow made in mortal fear was not binding, not even according to Medieval canon law", Feldmann concludes.