The obscure monk became a famous theologian at the centre of an international movement that would leave the church in the West permanently divided. On 31 October 1517 Luther posted on the door of the Castle Church of Wittenberg ninety-five theses protesting against the selling of indulgences and calling for a public debate on this issue. Luther was incensed because members of his own church had purchased indulgences from the Dominican Johann Tetzel. Luther attacked the assumption that forgiveness