The revelation
גְּאוּלָּה
When the World Knows Where It Is
Hashem does not become One in the future. His Oneness becomes openly perceived.
Nothing new arrives
Classical Sourceוְהָיָה ה׳ לְמֶלֶךְ עַל כָּל הָאָרֶץ בַּיּוֹם הַהוּא יִהְיֶה ה׳ אֶחָד וּשְׁמוֹ אֶחָד
And the L-rd shall be King over all the earth; on that day the L-rd shall be One and His name One.
It is easy to read the Messianic promise as a rescue: a world abandoned to itself, and then, at the end, an intervention from outside.
The sources describe something different, and the difference is not a detail. Hashem does not become One. Creation does not begin to depend on Him. The world does not become Divine.
What changes is perception — not in the weak sense of a shift in opinion, but in the strong sense that the concealment which constitutes exile is lifted. The verse in Zechariah says בַּיּוֹם הַהוּא יִהְיֶה ה׳ אֶחָד וּשְׁמוֹ אֶחָד — on that day His name will be one, which is to say: the way He is known will finally correspond to the way He is.
Geulah does not create Divine Unity. It reveals it.
The earth filled with knowledge
Classical Sourceכִּי מָלְאָה הָאָרֶץ דֵּעָה אֶת ה׳ כַּמַּיִם לַיָּם מְכַסִּים
For the earth shall be filled with the knowledge of the L-rd as the waters cover the sea.
Yeshayahu describes the Messianic condition as the earth being filled with דֵּעָה אֶת ה׳ as the waters cover the sea, and the image is precise in a way that is easy to miss.
Water does not cover a sea bed the way a cloth covers a table. The sea bed is not concealed by an addition; it is a sea bed, and the water is what it is under. The comparison says that knowledge of G-d will not be something the world receives but something the world is in.
This is why the framework treats Da'at as the hinge of the whole account. Da'at is knowledge as attachment. The Messianic promise is not universal information about G-d. It is universal connection.
Transparent, not dissolved
Chassidic DevelopmentOne clarification is essential here, because the alternative is a serious error.
The world does not become Divine Essence. Creation is not absorbed, cancelled or revealed to have been an illusion. Matter remains matter, a person remains a person, and the physical world remains physically real.
What it becomes is transparent to Divine purpose. The same object, the same body, the same street — no longer presenting itself as self-explanatory.