There is a large limestone cave in Gargano, Italy, that was a site of pagan worship in Greek and Roman times. The story of how the cave was transformed into a church dedicated to St. Michael is partially told in a collection of stories called the Liber de apparitione Sancti Michaelis in Monte Gargano, which first appeared in the ninth century. It is also recorded in the Acta Sanctorum by the Bollandists, a Jesuit organization that has studied the lives of the saints since the mid-1600s. Additionally, in the Middle Ages, a very popular collection of stories about many saints, called The Golden Legend, was written. It included the stories about Michael from Gargano as well as his appearances in other places.
Likely around 490, a wealthy noble named Elvio Emanuele was searching for a bull that had wandered from his herd on the slopes of the mountain. He found it stuck in the entrance to a cave. Angry at the bull for being unmanageable, he tried to have it shot with an arrow by a servant, but somehow the arrow came back and struck the archer himself. (In another version of the story, Elvio shot the arrow himself.) The noble went to Bishop Maiorano of Sipontum — who was later canonized and is now known as St. Lorenzo Maiorano — and recounted the strange events. The bishop, sensing something supernatural was afoot, ordered three days of prayer and penance.
At the end of the third day, St. Michael appeared to the bishop, saying:
Know ye that this man is so hurt by my will. I am Michael the archangel, which will that this place be worshipped in earth, and will have it surely kept. And therefore I have proved that I am keeper of this place by the demonstrance and showing of this thing.
After this apparition, the people and the bishop made a procession to pray at entrance of the cave. Two years later, likely in 492, the region was attacked by Odoacer and the Christian forces were all but defeated. Bishop Maiorano negotiated a three-day truce with the barbarians, during which the people prayed and did penance. But then St. Michael appeared to the bishop and promised help if they would attack the enemy. During the ensuing battle, a storm of sand and hail broke out that terrified the barbarians, who fled.
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