I will honestly admit, this is a very difficult passage. If read literally, it would make it way easier. You will probably disagree with how I view it, but none the less, you asked for me to respond to, so I will.
I will also be honest about assumptions on these verses. There are several assumptions that I made below. There are several non assumptions (AKA living waters = holy spirit, heavenly Jerusalem)
The Lord has gathered armies against Jerusalem multiple times (Assyria, Babylon, Seleucids....), the final destruction of Jerusalem
under the old covenant took place from 66-70 AD by the Romans.
If we read literally that the Lord will go forth and fight, then yes you are correct, God himself must come down from heaven to literally fight other armies.
However, then we must read Micah 1:3-5 literally That the Lord came literally to destroy Israel along with the Assyrians.
Micah 1:3-5
Judgment Against Samaria and Jerusalem
3Look!
The Lord is coming from his dwelling place;
he comes down and treads on the heights of the earth.
4The
mountains melt beneath him
and the
valleys split apart, like wax before the fire, like water rushing down a slope.
5All this is because of Jacob’s transgression, because of the sins of the people of Israel. What is Jacob’s transgression? Is it not Samaria? What is Judah’s high place? Is it not Jerusalem?
This one I will admit, is harder to understand, as there are multiple non-literal interpretations on it.
So I will just leave a quote from Eusbius
“And the words, ‘And his feet shall stand in that day on the Mount of Olives, which is before Jerusalem to the eastward,’ what else can they mean than that the Lord God, that is to say the Word of God Himself, will stand, and stand firm, upon His Church, which is here metaphorically called the Mount of Olives?”
“That the Mount of Olives shall be divided, half of it to the east and towards the sea, a very great chasm and half of it shall lean towards the north, and half of it towards the south,” it possibly shews the expression of the Church throughout the whole inhabited world, for it has filled the east, and the western and eastern nations; it stretches to the western sea, and the isles therein; yea, it has reached to west and south, and to north and north-east. On all sides and everywhere the Church figuratively called the Olive of the Lord is planted.
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Understand that verse 8 talks about
living waters flowing from Jerusalem. We know living water is the Spirit.
John 7:38-39 Whoever believes in me, as
f the Scripture has said, ‘Out of his heart will
flow rivers of living water.’” 39Now this he said about the Spirit, whom those who believed in him were to receive, for as yet the Spirit had not been given, because Jesus was not yet glorified.
Earthly Jerusalem can be destroyed, but not the heavenly Jerusalem.
Galatians 4:25-26
Now Hagar stands for Mount Sinai in Arabia and corresponds to the
present city of Jerusalem, because she
is in slavery with her children.
26But the
Jerusalem that is above is free, and she is our mother
Hebrews 12:22
But you have come to Mount Zion, to the city of the living God, the
heavenly Jerusalem.
Zechariah is using OT Law language to show a future spiritual truth. Christ is the fulfillment of the festivals. The truth being shown here is that people from all nations will come to the heavenly Jerusalem and worship the true God, even those form Eygpt (how had enslaved Israel).
Additionally, when understanding that there is no need for animal sacrifice because of Jesus, we can see the spiritual truth in this verse.
Colossians 2:16
16Therefore let no one judge you by what you eat or drink, or with regard to a
festival, a New Moon, or a Sabbath.
17These are a shadow of the things to come, but the body that casts it belongs to Christ.
All these are fulfilled in Christ.
