The prophet Yeshaya tells us (????? ??:?):
?? ??? ??? ???? ???? ????? ???.
“For the day of vengeance is in my heart and the year for my redeemed ones is coming.”
The Talmud (Sanhedrin 99a) states:
??? ??? ??? ????? ???’ ??? ????? ?? ???? ???: ???? ?????, ?????? ???? ?? ?????.
“What is meant by the day of vengeance is in my HEART? Reish Lakish said: I [HaShem] have revealed it to my heart, but not to the angels.”
The Midrash (Breishis Rabba 65:12) says:
???? ????? ?????? ???? ??? ???’ ?????? ????? ????? ????? ???’ ????? ?? ??? ??? ????.
The Midrash (Shocher Tov 9:2) says:
?’ ????? ???? ??? ?’ ?????: ?? ???? ?? ??? ??? ?? ?????? ???, ?? ????? ??, ??? ????? ?? ??? ??? ????, ???? ????? ?? ???, ???? ???? ???.
“R’ Shmuel learned in the name of R’ Yehuda: If someone tells you when the final redemption is coming, do not believe him, as it says, the day of vengeance is in my heart. The heart did not reveal it to the mouth, to whom could the mouth reveal it?”
Therefore, nobody could know when the redemption is to arrive. Rather, every day we need to pine and look forward to its arrival in the future, whether it is to arrive today or in fifty years.
Rav Yaakov Kaminetzky zt”l was asked: When is Moshiach coming? He answered: Those who know, do not say. Those who say, do not know.