Jamieson, Fausset and Brown on Ezekiel 40:2

2. visions of God--divinely sent visions.

very high mountain--Moriah, very high, as compared with the plains of Babylon, still more so as to its moral elevation (Eze 17:22; 20:40).

by which--Ezekiel coming from the north is set down at (as the Hebrew for "upon" may be translated) Mount Moriah, and sees the city-like frame of the temple stretching southward. In Eze 40:3, "God brings him thither," that is, close up to it, so as to inspect it minutely (compare Re 21:10). In this closing vision, as in the opening one of the book, the divine hand is laid on the prophet, and he is borne away in the visions of God. But the scene there was by the Chebar, Jehovah having forsaken Jerusalem; now it is the mountain of God, Jehovah having returned thither; there, the vision was calculated to inspire terror; here, hope and assurance.