The Vatican will display the papal ruling to excommunicate Germany\'s Martin Luther dated January 3, 1521 in an exhibition of hundreds of priceless documents from its secret archives from February 2011.A website for the exhibition said Pope Leo X\'s famous decree entitled \"Decet Romanum Pontificem\" -- which sealed a schism with Protestants and sparked a series of religious wars -- will be one of the most important objects on display. Organisers of the exhibit -- entitled \"Lux in Arcana\" -- said more rare documents to go on display would be revealed soon. The Vatican has said it wants to include documents that do not necessarily reflect well on its history.Among the displays will be Gregory VII\'s \"Dictatus Papae\" from the 11th century in which the pontiff affirmed the supremacy of popes over any power on earth as well as documents linked to Pius XII\'s pontificate during World War II. The exhibition will run for seven months in the Capitoline Museums.