"Three things cannot be long hidden: the sun, the moon, and the truth."
The Kabbalah says that when Moshiach will reveal himself "the rest of the world won't recognize him as such. Afterward he will be revealed again and wholly recognized."
In the Book of Daniel the Prophet, the famous commentator Rashi says "there will come a time when our King Moshiach will be concealed after he has been revealed and then he will return and reveal himself again." This applies to the present situation in which we find ourselves.
In the early 1990's, The Lubavitcher Rebbe instructed his followers to accustom themselves to Redemption with great and boundless joy. All obstacles and hindrances have been nullified and Moshiach, who is the Leader of our generation, not only exists, but in fact, is already revealed. We just need to welcome him in actuality with tangible action.
What can be more of a proof that this is a message that the Rebbe wants to deliver not only to his followers, but to everyone.
Final Test: Intuitive vs. Rational Mind
Today we find ourselves in the "concealment" stage - our physical eyes can't see the Lubavitcher Rebbe King Moshiach after his apparent "passing" in 1994. There is no successor either and understandably so: shortly before that, the Rebbe announced that since we were the last generation of exile and the first generation of Redemption, the concept of the soul leaving the body did not apply to the present Leader, hinting about himself. So we know and believe he is here just as before, however, to our eyes he seems to be concealed. And yet...
Since the Rebbe as a prophet told us that all obstacles and hindrances have been nullified, is there really concealment? Torah says that Mashiach "is standing behind our wall." He is watching and waiting in anticipation: When are we finally going to give the royal welcome?