Actually the Xtians do get the concept of the Anti-Messiah from us!
http://www.jewishencyclopedia.com/articles/1789-armilus
If you read Rav Kahane's "Jewish Idea" (Or Haraayon), you'll see he quotes the Torah sources about the Anti-Moshiach "Armilus" who will come from Rome and unite Edom, Yishmael, Gog, Erev Rav and Erev Katan in the final attack on the Kahanists (ie Torah-true Jews)!
According to that article on Jewish Encylopedia there is some belief that this idea came from Christianity first and was only later added to Jewish belief. I find some of it hard to comprehend considering the Unity of Hashem and the belief that Satan has no power aside from the power which Hashem grants it. The only reconciliation I can figure is that this is just another way of looking at the prophecy of Gog UMagog with a character named Armilus who is the general of Gog's army (as the Encyclopedia suggests).
Rubystars, here is a link to a document which discusses several of these 'apocolyptic' scenarios...
But the Talmud is clear that there can be two ways the final redemption comes, and this armilus idea is only relevant if the first way fails. The Talmud does say that the two ways are 'Before it's time' or 'at its appointed time', the first way if we merit the redemption, the second if we do not. The second way surely brings the war of Gog UMagog as the prophet Yehezkel tells us.
http://torahcode.us/torah_codes/moshiach/moshiach5.shtmlWe wait anxiously every day for the time of Redemption. When will it occur? The Kabbalists tell us
There is a potential end of days in every generation, according to its merits and a potential Messiah in the leader of each generation, according to the extent to which the people follow in his ways. If their sins become too numerous, the Redemption is postponed until a future time. (Tukkunei Zohar Chadash 95a)
Thus there have been many times which were propitious times for the Redemption. Rabbi Glazerson in his book Time for Redemption writes about the times that previous sages thought propitious for the Redemption. All these times have passed. Now, however, the time must be close. For many of the signs that the sages have written about are already present.
In the period preceding the coming of the Messiah, insolence will increase and honor wane. Prices will spiral upward. The vine will yield its fruit, yet wine will be expensive. The government [of Israel] will turn to heresy, but rebuke will be nonexistent. Meeting places will become places of sexual immorality. The Galilee will be destroyed, and the Gavlan desolated. Residents of border towns will go from place to place but find no haven. The wisdom of the sages will deteroiate, and those who fear sin will be despised. Truth will be lacking. Youths will put elders to shame. The elderly will stand up for the young. A son will treat his father disgracefuly. A daughter will rise up against her mother, a daughter-in-law against her mother-in-law, and a man's enemies will be members of his own household. The face of the generation will be like the face of a dog. A son will have no shame before his father.
Upon what can we rely? Only upon our Father in heaven. (Sota 49b)
http://www.arigoldwag.com/krentzman/Gog%20and%20MaGog.pdf
Within this period of “Acharis HaYamim” the phenomenon called “Chevley Mashiach”, “the Birth pangs of Mashiach”, is manifest. During this time, the Jewish people must endure great difficulties and oppressors, likened to a woman's pains of birth. It is also during this time that the initial “Kibbutz Galuyos”, “ In-gathering of the Jewish Exiles” back to Eretz Yisrael, takes place.
Out of the “Birth pangs of Mashiach”, Mashiach is “born” so to speak. He reveals himself and takes on his function as the king and leader of the Jewish people, restoring the spiritual state of the nation, through the restoration of the avodah of the Beis HaMikdash and bringing about the nation's fulfillment of the Torah and mitzvos, in their totality. Thus, we have “Bias HaMashiach”, “the Coming of Mashiach”.
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Brief Overview: In Yechezkel (32, and 38-39) the prophet describes a leader named Gog, from the land of Magog, who will lead a large array of armies in a cataclysmic war against the Jewish people in Eretz Yisrael. There will ultimately be great devastation, particularly among the legions of Gog. G-d will bring about a severe retribution against Gog and the nations that follow him and those who remain will come to recognize G-d, and His total providence, as a result. They will no longer oppress the Jewish people, and will recognize G-d's unique plan for His chosen people. In Zecharyah (14) the prophecy concerning Gog and Magog is concluded with the full restoration and Redemption of the Jewish people (and presumably the coming of Mashiach) and the nations of the world worshiping G-d in the Beis HaMikdash, on the holiday of Succos, alongside the Jewish people.
Information about the 'two Moshiachs' Moshiach Ben Yosef and Moshiach Ben David:
http://www.chabad.org/library/moshiach/article_cdo/aid/101747/jewish/Appendix-II.htm#footnoteRef5a101747Jewish tradition speaks of two redeemers, each one called Mashiach. Both are involved in ushering in the Messianic era. They are Mashiach ben David and Mashiach ben Yossef.1
The term Mashiach unqualified always refers to Mashiach ben David (Mashiach the descendant of David) of the tribe of Judah. He is the actual (final) redeemer who shall rule in the Messianic age. All that was said in our text relates to him.
Mashiach ben Yossef (Mashiach the descendant of Joseph) of the tribe of Ephraim (son of Joseph), is also referred to as Mashiach ben Ephrayim, Mashiach the descendant of Ephraim.2 He will come first, before the final redeemer, and later will serve as his viceroy.3
The essential task of Mashiach ben Yossef is to act as precursor to Mashiach ben David: he will prepare the world for the coming of the final redeemer. Different sources attribute to him different functions, some even charging him with tasks traditionally associated with Mashiach ben David (such as the ingathering of the exiles, the rebuilding of the Bet Hamikdash, and so forth).4
The principal and final function ascribed to Mashiach ben Yossef is of political and military nature. He shall wage war against the forces of evil that oppress Israel. More specifically, he will do battle against Edom, the descendants of Esau.5 Edom is the comprehensive designation of the enemies of Israel,6 and it will be crushed through the progeny of Joseph. Thus it was prophesied of old, "The House of Jacob will be a fire and the House of Joseph a flame, and the House of Esau for stubble.." (Obadiah 1:18): "the progeny of Esau shall be delivered only into the hands of the progeny of Joseph."7
See also :
http://download.yutorah.org/2008/1053/726192.pdf is a very detailed explanation of the various prophecies...