Belief in the Old Testament precludes belief in the New Testament or Koran

Proof #1My opponent states: "[W]hether God spoke is almost irrelevant." In such case, I will not waste time by addressing points which my opponent concedes are irrelevant. Instead, I will focus on other aspects, namely that the events that transpired set a standard to which other similar events should adhere to. In this case: prophets being accompanied by weather or other natural phenomenon. My opponent argues that since this was never duplicated, no prophets of the New Testament or Koran should be accepted.However, we should also note that, for the purposes of this debate, we are accepting the contents of the Old Testament as true. "[I]f you believe in the Old Testament's divinity, ala traditional Christianity or Islam, and that what it says is true..."Given that, it is a simple matter of enumerating prophets who were the recipient of divine revelation and then passed on God's word to others, and to determine if those circumstances matched the events at Mt. Sinai.Gad:"Before David got up the next morning, the word of the LORD had come to Gad the prophet, David’s seer: “Go and tell David, ‘This is what the LORD says: I am giving you three options. Choose one of them for me to carry out against you.’” - 2 Samuel 24:11 & 12Now. God did act through natural phenomenon (plague) along with this revelation, but afterwards, in response to David's choice. This is not in line with the events of Mt. Sinai, where God revealed himself to the masses prior to revelation.The Man of God:"By the word of the LORD a man of God came from Judah to Bethel, as Jeroboam was standing by the altar to make an offering. By the word of the LORD he cried out against the altar: “Altar, altar! This is what the LORD says: ‘A son named Josiah will be born to the house of David. On you he will sacrifice the priests of the high places who make offerings here, and human bones will be burned on you.’”That same day the man of God gave a sign: “This is the sign the LORD has declared: The altar will be split apart and the ashes on it will be poured out.” When King Jeroboam heard what the man of God cried out against the altar at Bethel, he stretched out his hand from the altar and said, “Seize him!” But the hand he stretched out toward the man shriveled up, so that he could not pull it back. Also, the altar was split apart and its ashes poured out according to the sign given by the man of God by the word of the LORD.Then the king said to the man of God, “Intercede with the LORD your God and pray for me that my hand may be restored.” So the man of God interceded with the LORD, and the king’s hand was restored and became as it was before." - 1 Kings 13:1-6Again, unusual events that come after the revelation, validating it.Now, it would be inappropriate to go through all the prophets as several dozen are recognized in the Old Testament alone (1).Now, to develop a true standard would involve examining the circumstances revolving around all of the accepted prophets and seeing what common elements are among them. I believe such is outside the scope of this argument. As we can see above, all that is truly necessary is that god speak to/through this individual. In short, if there is a standard for identifying or accepting prophets. It is pretty loose. Nothing so strict as to outright deny the possible validity of the New Testament or Koran.Proof #2It is not enough to simply enumerate the conditions on which a prophet should be identified as false and rejected (and put to death) but we must determine whether or not the prophets of the New Testament or Koran violate those principles. In short, based on what you've provided above, a false prophet: Makes a prediction that is false (though true predictions are not guarantees of validity) Encourages worship of other gods. Otherwise incites rebellion against god and/or his commandments. Regarding the last statement: "See that you do all I command you; do not add to it or take away from it." While it is indeed a blanket statement, we should also consider the speaker, and the context and scope in which it was spoken. It was not a statement spoke to or about prophets, but to the people as a warning when they encounter other gods worshipped in other ways. It cannot be taken in a strictly literal and universal manner, or the Old Testament would have ended right then and there. Also consider that many accepted Old Testament prophets after Moses gave commands ostensibly from god. A strict interpretation would then rule them out as prophets, but we can't do that as we are treating the Old Testament as true for this argument.In any event, how does either Jesus or Mohammed violate the principles outlined above? Did they make false predictions? Did they encourage the worship of other gods? Did they incite rebellion against god? It would seem that you have a burden to demonstrate this.SummaryI commend my opponent for the level of effort and research he has put into his proofs. However, at the end I see that they only established conditions and limitations on future prophets, that that any future prophet is necessarily false. Having established these conditions, I assert that this is only half the argument. It must be further demonstrated that the prophets of the New Testament or Koran violate those principles.[1] http://www.jewfaq.org...