Question:

Is the ability to perform miracles one of the signs that will identify Moshiach?

Answer:

We find by our first redeemer, Moses, there were a number of signs that G-d gave him to perform to prove that he was sent by G-d. On the other hand, Moses was also given code words to say, which the elders recognized by tradition to be a sign of the redeemer. The three signs that G-d gave Moses to perform were: his stick became a snake; his hand became leprous, and he transformed water to blood. Therefore, there is room to believe that the final redeemer, Moshiach, will likewise be given signs.

Halachically, though, Maimonides rules explicitly: "Let it not enter your mind that King Moshiach needs to perform signs or miracles or innovate things in this world, or revive the dead or the like... the matter is not so. Rabbi Akiva was a great scholar, of the scholars of the Mishnah, and he was one of the supporters of Ben Koziva.. It appeared to him and to all the scholars of his generation that he was Moshiach, and the wise men did not ask him for any signs or miracles!"

Rabbi Avraham ben David, a commentator on Maimonides, questions his words, and brings a proof from the words of our sages that Ben Koziva was put to death by the sages themselves when he failed to produce the signs required of Moshiach. It appears, then, that Moshiach will need to prove himself through signs and miracles.

However, other commentators on Maimonides explain that he ruled according to the other opinions mentioned in the Talmud, that Ben Koziva was killed by non-Jews and not by the sages. According to this opinion, Moshiach does not have to demonstrate any signs, since "there will be no difference between now and the days of Moshiach, except that we will no longer be subjugated to the nations.

Sources: Shmos 4:2. Sanhedrin 93b. Yerushalmi, Taanis, 4:5. Eicha Rabba, 2:2. Hilchos Melachim, 11:3, see also commentary by Raavad and others. Likutei Sichos vol. 13, p. 297, footnote 14 and vol. 27, p. 200 footnote 69.