The mountain of the house of the Lord

There are some striking parallels between Eden and the temple in Ezekiel. To begin with, both Eden and the temple are situated on mountains:

40 In the twenty-fifth year of our exile, at the beginning of the year, on the tenth day of the month, in the fourteenth year after the city was struck down, on that very day, the hand of the Lord was upon me, and he brought me to the city. 2 In visions of God he brought me to the land of Israel, and set me down on a very high mountain, on which was a structure like a city to the south (Ezk 40:1-2). 

13 You were in Eden, the garden of God;
    every precious stone was your covering,
sardius, topaz, and diamond,
    beryl, onyx, and jasper,
sapphire, emerald, and carbuncle;
    and crafted in gold were your settings
    and your engravings.
On the day that you were created
    they were prepared.
14 You were an anointed guardian cherub.
    I placed you; you were on the holy mountain of God;
    in the midst of the stones of fire you walked (Ezk 28:13-15).

So Eden is a type of shrine or sanctuary. A prototype of the temple. 

Here's a different parallel:

47 Then he brought me back to the door of the temple, and behold, water was issuing from below the threshold of the temple toward the east (for the temple faced east). The water was flowing down from below the south end of the threshold of the temple, south of the altar (Ezk 47:1). 

A river flowed out of Eden to water the garden, and there it divided and became four rivers (Gen 2:10). 

Although Ezekiel's imagery is mainly symbolic, it probably has a basis in fact. It's natural to view the rivers or tributaries of Eden as mountain streams. 

In addition, the temple was erected on a hill: "Mt Zion." In prophetic imagery, this assumes a hyperbolic elevation:

It shall come to pass in the latter days    that the mountain of the house of the Lordshall be established as the highest of the mountains,    and shall be lifted up above the hills;and all the nations shall flow to it (Isa 2:2).

Here's another parallel:

Exactly as I show you concerning the pattern of the tabernacle, and of all its furniture, so you shall make it (Exod 25:9). 

11 Then David gave Solomon his son the plan of the vestibule of the temple, and of its houses, its treasuries, its upper rooms, and its inner chambers, and of the room for the mercy seat; 12 and the plan of all that he had in mind for the courts of the house of the Lord, all the surrounding chambers, the treasuries of the house of God, and the treasuries for dedicated gifts (1 Chron 28:11-12).

Commentators generally agree that the word "pattern" denotes, not a set of verbal instructions, but a replica. That would dovetail with God "showing" Mosaic what to do. 

In other words, God gave Moses a vision of tabernacle. An archetypal tabernacle, on which the earthly tabernacle was modeled. 

This might suggest vertical typology, where the terrestrial tabernacle and temple copy celestial exemplars. Earthly counterparts to heavenly archetypes. And, indeed, the Bible uses that imagery:

2 Hear, you peoples, all of you;    pay attention, O earth, and all that is in it,and let the Lord God be a witness against you,    the Lord from his holy temple.3 For behold, the Lord is coming out of his place,    and will come down and tread upon the high places of the earth (Micah 1:2-3).

They serve a copy and shadow of the heavenly things. For when Moses was about to erect the tent, he was instructed by God, saying, “See that you make everything according to the pattern that was shown you on the mountain” (Heb 8:5; cf. 9:23-24). 

i) This doesn't mean Bible writers thought there was a physical temple in the sky or above the sky. To some extent, the sky itself is the temple. The earthly tabernacle or temple is, in part, a symbolic representation of the vast, illuminated cosmos. 

Bible writers view God as essentially bodiless. So it's not as if they thought God really dwelt in a heavenly temple. 

So what did Moses and Ezekiel see? Presumably, they saw God's idea of the tabernacle and temple. God has ideas of everything. He showed them his idea. In a way, he let them peer into his own mind. 

ii) In that sense, Ezekiel vision of the temple is not, in the first instance, about the future, but the present or the past. About what's always been, and always will be. What already exists. Forever subsisting in God's eternal mind. Existing in God's timeless imagination. 

If you could look into God's mind, what would you see? You'd see the history of the world. You'd see alternate histories. Ideas of unexemplified possibilities. What might have been, but never was. God's infinite mind is the ultimate source of all possibilities and actualities. In that sense, Ezekiel's vision is retrospective rather than prospective–which doesn't preclude a future realization in time and space.

iii) This may also explain how the Genesis narrator got some of his information about primordial or prediluvian history: by direct revelation. If God gave Moses a vision of the tabernacle, why not a vision of Gen 1, or Gen 2-3, &c.? 

By the same token, revelatory dreams figure frequently and prominently in Genesis (e.g. Abimelech, Jacob, Joseph, Egyptian baker, cupbearer, Pharaoh).

That doesn't rule out Moses using ancestral records for some of the material in Genesis. But in some cases, visionary revelation would be a simpler explanation. 

One potential objection to this explanation is that visionary accounts typically say the speaker or writer saw this in a dream or vision. 

However, that objection overlooks the fact that a Biblical narrator typically recounts events from a third-person perspective. Even if he was an active participant, he assumes the detached voice of a third-person reporter. He doesn't break that literary convention with first-person interjections.