Ezekiel 37:10 So I prophesied as he commanded me, and breath entered them; they came to life and stood up on their feet--a vast army.
Where did they go afterward? Was it just an immaterial vision that disappeared at the end of the vision?
In understanding Ezekiel's prophecy of the valley of dry bones (Eze 37:1-14) we must decide, in the first instance, whether the prophecy is literal or symbolic.
The prophecy is literal then it has not been fulfilled as no such valley thickly strewn with dry bones over the ground exists. Further, if the vision is of literal events, then it depicts a very strange resurrection involving restored bodies without breath (v8). Further, before their resurrection, the dead, dry bones speak and say (V11), "Our bones are dried up, and our hope has perished; we are cut off."
On the other hand, if we understand that the vision is symbolic ["The vision is so entirely figurative" MacLaren's exposition on Eze 37:1], then it clearly emblematic of Israel's restoration after the Babylonian captivity. This is the clear understanding of most conservative commentators such as:
MacLaren's Exposition:
This great vision apparently took its form from a despairing saying, which had become a proverb among the exiles, ‘Our bones are dried up, and our hope is lost: we are clean cut off’ {Ezekiel 37:11}. Ezekiel lays hold of the metaphor, which had been taken to express the hopeless destruction of Israel’s national existence, and even from it wrings a message of hope.
Benson observes:
The first and great object of this prophecy seems evidently to be the restoration of the Jews from the Babylonish captivity. A nation carried into captivity ceases to be a nation, and therefore may be fitly compared to bones, or dead bodies; so that by the valley of bones was first signified, the Babylonish dominions filled with captive Jews.
Barnes:
The "dry bones" represented the Israelites dispersed abroad, destitute of life national and spiritual.
Cambridge:
The vision seems suggested by the saying current among the people, “our bones are dried, our hope is lost; we are wholly cut off.” This idea and feeling of the people takes form in the vision which the prophet saw in the valley. The language of the people is figurative: they speak of the nationality, which is no more,—it is dead and its bones scattered and dry. And this idea regarding the nationality, figuratively expressed by the people, is embodied to the prophet in a vision. Hence the passage is not a literal prophecy of the resurrection of individual persons of the nation, dead or slain; it is a prophecy of the resurrection of the nation, whose condition is figuratively expressed by the people when they represent its bones as long scattered and dry.
Indeed, V11 specifically says that, "Son of man, these bones are the whole house of Israel. Look, they are saying, ‘Our bones are dried up, and our hope has perished; we are cut off.'"
With this understanding, Ezekiel's vision is symbolic of the time that Judah's national fortunes would be restored. Ezekiel specifically says that the LORD would (V14),
"I will put My Spirit in you and you will live, and I will settle you in your own land. Then you will know that I, the LORD, have spoken, and I will do it, declares the LORD."
Ezekiel's prophecy of the restored state of Israel was fulfilled with the decree of Cyrus recorded in Ezra 1 and implemented by Zerubbabel as recorded in Ezra 2 & 3 and still later by Nehemiah.
Was the army in Ezekiel 37:10 physical?
NO, the vision is symbolic, the Israelites were spiritually dead in exile and God revitalized them spiritually by putting his spirit in them. (Vs14) and so they began to come alive.
When the Babylonians destroyed Jerusalem, Ezekiel was one of the Israelites captives taken to Babylon, during the captivity he was given by God the symbolic vision of the valley of the dry bones. (Ezekiel 37:1-10) When prophecied as commanded, the bones started to come together and becoming covered with sinews flesh and skin. The vision is explained in Ezekiel 37:11-14.
The Israelites saw the fulfillment of the prophecy when Babylon was captured by the Persians, (Ezra 1:1-4, 2;64-65)God delivered them from their captivity and lead them back to Israel. Being in captivity the people of Israel were spiritually dead due to their Babylonian exile, but God put his spirit in his people (Vs14) so they became spiritually alive.
Recommend reading the prophecy Ezekiel 37:1-10 and explanation given by God to his prophet.Ezekiel 37: 11-14
https://classic.biblegateway.com/passage/?search=Ezekiel+37%3A1-14&version=NASB;NET
The Vision Explained Ezekiel 37:11-14 NASB
11 Then He said to me, “Son of man, these bones are the whole house of Israel; behold, they say, ‘Our bones are dried up and our hope has perished. We are [e]completely cut off.’ 12 Therefore prophesy and say to them, ‘Thus says the Lord God, “Behold, I will open your graves and cause you to come up out of your graves, My people; and I will bring you into the land of Israel.
13 Then you will know that I am the Lord, when I have opened your graves and caused you to come up out of your graves, My people. 14 I will put My [f]Spirit within you and you will come to life, and I will place you on your own land. Then you will know that I, the Lord, have spoken and done it,” declares the Lord.’”
The army in Ezekiel's prophetic vision depicts the host of believers upon whom the Holy Spirit would fall following Jesus' ascension, empowering them to go and preach the Gospel in obedience to his commission:
Acts 1:8 (KJV)
But ye shall receive power, after that the Holy Ghost is come upon you: and ye shall be witnesses unto me both in Jerusalem, and in all Judaea, and in Samaria, and unto the uttermost part of the earth.