• Possibility that Moshiach will come suddenly – R' Saadia Gaon, Sefer Emunos v'Deos 8:6, "...if we will return to G-d...Moshiach ben Dovid will be revealed to us instantly." Talk of the Lubavitcher Rebbe, Parshas Pinchas 5744, "Rambam says that there is a set order for Moshiach’s coming...when, however, Jews merit it, and especially since 'all the fixed dates [for Moshiach’s coming] have passed,' then the redemption comes immediately, transcending all limits and order. • Also, 4 Elul 5750 "...both the commencement of the redemption and its completion are concurrent... we will have the beginning and its completion immediately..."
• Do all the mitzvos – The Arizal (Sefer HaGilgulim, ch. 4) as brought in Tanya, Igeres Hakodesh, ch. 29: "every Jew needs to be reincarnated many times, until he will fulfill all 613 commandments of the Torah in thought, speech and action."
• Even one tzaddik – Rebbe Schneur Zalman of Liadi wrote, based on the Zohar Chadash: "even if there was one tzaddik that did complete tshuva in his generation, Moshiach would come."
• "The bad-guys won't need to be killed – Reishis Goyim Amalek by Rebbe Yosef Yitzchok Schneersohn, "...there is a difference between Moshiach's coming 'at the appointed time' and his coming 'in haste' before the 'appointed time'. If the kelipot are nullified 'at the appointed time', they will be utterly annihilated. If, however, the Jewish people are found worthy and Moshiach comes 'in haste' at an earlier than the appointed time, then the kelipot will be nullified by being rectified."
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