The Spear of Destiny (as seen in the movie Constantine) is the spear that pierced Jesus' side and killed him1,and apparently is a divine force capable of releasing the Apocalypse according to Corinthians chapter 17 (don't waste your precious time: there is no Corinthians 17, it was a plot device for the movie). the non-existent Corinthians 17 says that Mammon, the son of Lucifer, would release Hell on earth after crossing onto our Plane from the Hell Plane2;. But in order to do this, he would need divine help. Apparently, the blood stains on the spear was enough divine aid to give Mammon the power to cross onto our Plane, and release all of Hell with him. There are obvious problems in this use and idea of the Spear of Destiny.
The Spear of Destiny was an actual spear, guided by Saint Longinus into the side of Jesus but didn't kill him1. The movie also said that the Spear of Destiny has been missing since World War II, when it was actually discovered in Adolf Hitler's office (he ordered it brought to him after he annexed Austria in March 19383) when American troops invaded his office (April 30th, 1945, at 2:10 PM---a mere 80 minutes before Hitler committed suicide). The spear was returned to its former home in the Hofburg Museum, where it has rested ever since.
1: "So the soldiers went and broke the legs of the first man and then of the other man who had been crucified with Jesus. But when they came to Jesus, they saw that
he was already dead, so they did not break his legs. One of the soldiers, however, plunged his spear into Jesus' side, and at once blood and water poured out. (The one who saw this happen has spoken of it, so that you also may believe. What he said is true, and he knows that he speaks the truth.)
"
John 19:32-35~Good News Translation---courtesy www.crosswalk.com
2: See
Planes of Reality and
plane of existence
3: For more on
Hitler and the spear, and other people's experiences with it, go to http://www.unmuseum.org/spear.htm