Before the Messianic Era, the earth will be in a state of chaos and decay, as the prophet Isaiah said, "The foundations of the earth shake, the earth is completely broken down, the earth crumbles away, the earth continually falters, the earth reels to and fro like a drunkard." G-d will send Moshiach to bring stability to the world.(Ibn Ezra, Psalm 96)
(L'Chaim)

When good triumphed over evil in the past, evil was not utterly vanquished. For example, the impure spirit still pervaded the atmosphere of Egypt even after the Egyptians were annihilated at the sea. The same was true after Israel's other victories over their enemies. In the future, however, the atmosphere will be completely purged of every detrimental influence.(Alshich on Psalm 96)
(L'Chaim)

Whoever achieves perfection in these traits; in that his eye sees the good in all, and he is modest; he is worthy of sovereignty. In this manner G-d fashioned David to be His anointed king. And this is to be the character of Moshiach, the son of David, who will speedily be revealed to us.(The Book of Our Heritage)
(L'Chaim)

When the earth was cursed at the time of the sin of the Tree of Knowledge, many flourishing fruit trees became barren; thenceforth entire species of trees brought forth only brambles and thorns. The Talmud teaches, however, that all of these barren trees will eventually produce luscious fruit and that those who behold this wonder will sing joyously in the times of Moshiach.
(Alshich on Psalm 96)
(L'Chaim)

"Then all the trees of the forest will sing joyously." (Psalm 96:12) Rashi explains that the trees of the forest symbolize the monarches of the gentile nations. With their strength and erect bearing, they resemble towering trees. They, too, are destined to recognize the sovereignty of Moshiach, and they shall rejoice when he arrives.
(L'Chaim)

"What is our task now? There only needs to be the acceptance of Moshiach's kingship by the people, and the devotion and attachment between the king and the people in a most revealed sense."(The Rebbe, Shabbat Mishpatim, 5751)
(L'Chaim)

Just as we find that Moses ascended to heaven, body and soul... similarly, Moshiach will, through the help of G-d, merit to attain that lofty soul. He will then realize that he is in fact Moshiach, although no one else will be aware of this... Shortly afterwards, Moshiach will be hidden away, body and soul, in that Divine pillar, as previously explained... Moshiach will thereupon rise up to heaven just as Moses ascended to the firmament, and will subsequently be revealed completely for all to see. The entire Jewish people will then perceive him and flock towards him.(Arba Meiot Shekel Kesef p. 68)
(L'Chaim)

The liberation of the 12th of Tammuz will lead us to the ultimate redemption. Every salvation bears the name "redemption," as such it has a common denominator with every other salvation. Thus, the redemption of the Nasi [leader of the generation] is associated with the ultimate and true redemption; through our increased efforts to disseminate Torah and strengthen Judaism the master [Moshiach] will come.(The Rebbe, 14 Tammuz, 1987)
(L'Chaim)

Nine red heifers were prepared...: the first was prepared by Moses, the second by Ezra, and there were seven from the time of the Ezra until the Destruction of the [second] Holy Temple. The tenth will be prepared by the King Moshiach -- may he speedily be revealed! Amen, may this be G-d's will!(Maimonides, Laws of the Red Heifer, 3:4)
(L'Chaim)

Return in mercy to Jerusalem Your city and dwell therein as You have promised; speedily establish therein the throne of David Your servant, and rebuild it, soon in our days, as an everlasting edifice. Blessed are You L-rd, who rebuilds Jerusalem.(From the "Shemona Esrei" prayer recited three times daily)
(L'Chaim)

The ultimate promise [of Redemption] is not to Israel alone. The Redemption of the Jew is closely linked to the emancipation of all humanity as well as the destruction of evil and tyranny. It is the first step in man's return to G-d, where all mankind will be united into "a single band" to fulfill G-d's purpose. This is the Kingdom of the Almighty in the Messianic Age.(The Real Messiah by Rabbi Aryeh Kaplan)
(L'Chaim)

Rabbi Levi Yitzchak of Berdichev would point out that the name Shabbat Chazon stems from the word "machaze," meaning "vision," for "on that day everyone is shown the future Beit Hamikdash." On Shabbat Chazon the transcendent root of the soul sees the future Holy Temple; moreover, this perception leaves an imprint on the individual, even on his body and on his animal soul.(Likutei Sichot, vol. 29)
(L'Chaim)

Sound the great shofar for our freedom; raise a banner to gather our exiles, and bring us together from the four corners of the earth into our land. Blessed are You L-rd, who gathers the dispersed of His people Israel.
(From the "Shmona Esrei" prayer said three times daily)
(L'Chaim)

"The death of the righteous is compared to the burning of the House of our L-rd." (Talmud Rosh Hashana 18b) The true intention of this epigram is that the tragedy of a Tzadik's passing is also a descent which must bring us closer to the building of the Third Holy Temple.(The Rebbe, 20 Av, 5747)
(L'Chaim)

Jews firmly believe that Moshiach will come. We believe that man will not self-destruct, that we will not disappear in a gigantic atomic blast. Man is basically good, and G-d's Kingdom will be established.(Rabbi Pinchas Stopler in The Real Messiah)
(L'Chaim)

Look with favor, L-rd our G-d, on Your people Israel and pay heed to their prayer; restore the service to Your Sanctuary and accept with love and favor Israel's fire-offerings and prayer; and may the service of Your people Israel always find favor. May our eyes behold Your return to Zion in mercy. Blessed are You, L-rd, who restores His Divine Presence to Zion.(From the Amidah prayer said three times daily)
(L'Chaim)

Moshiach signifies the separation of the good from the evil. This is why he will come "only in a generation which is altogether meritorious or altogether sinful"; i.e., at a time in which there will be no mixture of good and evil. So long as Moshiach has not come, there is a mixture of good and evil in all the worlds: there is no good without evil and no evil without good.(Short Maamarim of the Alter Rebbe, p. 403)
(L'Chaim)

Speedily cause the scion of David Your servant to flourish, and increase his power by Your salvation, for we hope for Your salvation every day. Blessed are You L-rd, who causes the power of salvation to flourish.
(From the Shemona Esrei prayer said 3 times daily)
(L'Chaim)

Rabbi Saadia Gaon gives as the tenth reason for sounding the shofar on Rosh Hashana: To recall our faith in the future resurrection of the dead. As it is said: "All you inhabitants of the world, and you who dwell in the earth; when an ensign is lifted on the mountains you shall see, and when the shofar is sounded you shall hear." (Isaiah 18)
(L'CHAIM)

The connection between the ultimate Redemption and Yom Kippur is reflected in that Yom Kippur is the tenth of Tishrei and the number ten is associated with several dimensions of the Era of the Redemption.(The Rebbe, the eve of Yom Kippur, 5752)
(L'Chaim)