BELIEF IN THE COMING OF THE MOSHIACH [HAZRAT MAHDI (AS)] IS A BASIC TENET IN JUDAISM

According to Rambam, belief in the coming of the Moshiach [Hazrat Mahdi (as)] is one of the thirteen basic tenets of Judaism. There are two distinct facets to this belief. One is the obligation to believe the Moshiach [Hazrat Mahdi (as)] will arrive. Second is the obligation to await the [Hazrat Mahdi (as)] Moshiach and to fervently hope for his arrival.

Though he may tarry, await him, for he will surely arrive; he will not delay.

[Chavakuk 2:3]

Rava said: When they bring to his [final] judgment, they ask him… “Did you await redemption?”

[Shabbos 31a]

The twelfth principle [deals with] the days of the Moshiach [Hazrat Mahdi (as)], that [a person is obligated] to believe and affirm that he will come…

[Rambam, Peirush haMishnayos, Sanhedrin, Chelek]

The belief in the coming of the Moshiach [Hazrat Mahdi (as)] is incumbent on every person who observes the Torah of Moshe… This is because the Torah explicitly mentions the obligation to believe the words of the prophets, as it says, “[A prophet from your midst… Hashem, your God, shall establish for you;] to him shall you listen” [Devarim 18:15], and the prophets prophesied the coming of the Moshiach [Hazrat Mahdi (as)]. It is clear that any person who does not believe in the coming of the Moshiach [Hazrat Mahdi (as)] denies the words of the prophets and transgresses a positive commandment.

[Sefer Halkarim 4:42]