The sages have said that in the seventh millennium since creation, very unusual things will happen in this world. Exactly what will happen then?

The famous Kabbalist Rabbi Moshe Alshich explains that, as described in the Torah, there are “upper waters” and “lower waters.” At first, both water layers were mixed. Then G-d created the firmament that separates between the two. The two layers of water allude to two types of wisdom: the wisdom of Torah, the upper wisdom, and natural wisdom, the lower layer. At first, the wisdom of Torah and the wisdom of science were blended together. Later, however, when the world became an independent, physical existence, there was a separation between Torah and natural wisdom. When Moshiach comes, natural science will be restored to its source and it will be revealed how it draws from the wisdom of Torah.

This is the meaning of the statement of our sages, that in the seventh millennium the world will be destroyed. The “arrogance” of the physical world and of scientific wisdom will be shattered. Both will recognize their common source in Torah and in holiness.

Our sages also write that “In those years, G-d will make wings for the tzadikim and they will float on the face of the waters. What if it is painful for them? The verse (Isaiah 30:31) states: ‘But those who put their hope in the Lord shall renew [their] vigor, they shall raise wings as eagles; they shall run and not weary, they shall walk and not tire.’”

The Alshich explains further: The tzadikim will be on such a high level that they will easily float, so to speak, over the sea of Torah. Just like the eagle, which is the only winged creature that carries its young on its back, G-d will elevate the Jews above the wisdom of the Torah, which is G-d’s own wisdom.

The Tzemach Tzedek writes: All this will transpire only in the seventh millennium, when G-d will renew His world. The physical world will be lost, and only the tzadikim will remain floating on the face of the water. However, afterwards the world will be renewed just like it is now, except that the Holy Temple will not be in ruins any longer and the Jews will no longer suffer oppression, since the world will be completely good.

(Sanhedrin 92a. Alshich Bereishis 1:2. Sefer Halikuttim Tzemach Tzedek, Charuv)