For example, what would disqualify the Prophet Sollog from being a true prophet?
Sollog the Prophet
From Wikipedia http://en.wikipedia.org/wiki/Sollog
Sollog claims to have predicted a large number of major events, including the crash of TWA flight 800, the Oklahoma City bombing, the death of Diana, Princess of Wales, the September 11 terrorist attacks, and the Space Shuttle Columbia disaster, as well as a wide range of natural disasters in the U.S.
Methods
On a map Sollog draws lines between cities in the United States, claiming a successfully predicted disaster for any hurricane that passes over one of these lines. For example, in 2002, he predicted that 17 particular hurricanes would hit 17 particular cities. [7] However, over half of these hurricanes had already passed without destroying any city, and the names will not be reused until 2010 at the earliest. Hurricane Katrina was notably absent from the list.
Sollog has also issued repeated predictions of specific events, without tying them to specific dates. These are subsequently assigned various dates by other people. A notable instance of such a claim is the death of Pope John Paul II, for which Sollog's claims had been interpreted as predictions for March 18 (without a year) [2], September 11, 1997 [3], and October 15, 1997 [4]. The alleged prophecies referred to in the links do not mention any specific dates. The pope died on April 2, 2005.
The 911 prediction
In a more notable Usenet posting, dated 11 September 1998 at 2:00 a.m., someone with the pseudonym of "eLnIn" writes, "SOLLOG SAYS THAT ON 911 THERE WILL BE A GREAT EMERCENCY IN WASHINGTON DC ANOTHER GARAUNTEE FROM SOLLOG THE GOD OF ONE!!!!! READ IT AND WEEP MORONS!!!!!"[8] Sollog states that this is a specific prediction of the 11 September 2001 attacks.[citation needed] Xinoehpoel, either a follower or an alter ego of Sollog, also predicted the attacks in the same Usenet newsgroup.
The Tsunami prediction
Another notable post is on the Tsunami disaster, which predicted two historic quakes killing thousands on 01/01/2005 and 03/21/2005. The 2004 Indian Ocean earthquake on December 26, 2004 killed over 180 thousand.
The SUSA prediction
From at least 1997 through 2000, various Usenet posters had submitted "THE SUSA PROPHECY by Sollog." This predicted the destruction of nine major U.S. cities by the year 2001. The text refers to American cities that are to be destroyed, saying "A Great Hurricane shall destroy New Orleans." [6] On January 24, 2004 a Usenet poster by the name of TruthSeeker later submitted the same "THE SUSA PROPHECY by Sollog" with the dates changed. [7] Given the geographic characteristics of New Orleans and the extensive history of hurricane activity in the Gulf of Mexico, the wake of Hurricane Katrina and devastation of New Orleans had been widely predicted by meteorologists and most civic leaders.
Now it could be argued that he isn't a prophet because he doesn't testify of Christ, but the dictionary definition of prophet doesn't mention anything about testifying of Christ.
Prophet
1. A person who speaks by divine inspiration or as the interpreter through whom the will of a god is expressed.
2. A person gifted with profound moral insight and exceptional powers of expression.
3. A predictor; a soothsayer.
4. The chief spokesperson of a movement or cause.
He definitely fits 3 and 4, and I don't know enough about him to know if he also fits 1 and 2. According to Wikipedia, he has gotten into some legal problems, and he used to work at a porno shop, but why should any of that change the fact that he is a prophet who can predict the future?