Zechariah 12:3 It will come about in that day that I will make Jerusalem a heavy stone for all the peoples; all who lift it will be severely injured. And all the nations of the earth will be gathered against it.

In that day? The day is likely not the Day of the Lord based on the context. The Day of the Lord has specific definition. It occurs after Elijah’s coming, after the Sun, moon and stars are darkened, after the coming of Antichrist. You can read about all of this in my book.

Is Armageddon spoken of here?  (see Rev. 16:14-16 if you doubt it). The fact that Armageddon is included here positions this day just before the day of the Lord. This nearness causes some to include in that day the entire Great Tribulation, of which Jesus also spoke. Are they correct? The Jews or a good portion of them must be back in the land for this to happen. Are they? Fact is –Yes, and No., so  are we actually in the prelude to this time spoken of here?

Zechariah 12:6, 9 “In that day I will make the clans of Judah like a firepot among pieces of wood and a flaming torch among sheaves, so they will consume on the right hand and on the left all the surrounding peoples, while the inhabitants of Jerusalem again dwell on their own sites in Jerusalem. And in that day I will set about to destroy all the nations that come against Jerusalem.
Some of this verse has and is occurring, but obviously more is to come, but (all) in these verses must not include every nation, nor does it include all people, because there are nations and people remaining based on Zachariah 14, and other of the prophets for Jesus to judge upon His return to earth.
Zechariah 13:1 “In that day a fountain will be opened for the house of David and for the inhabitants of Jerusalem, for sin and for impurity.
This fountain is the provision for sin already provided them by their Messiah, but now in this day it is opened up to them. Today they are blinded by their unbelief.  These scriptures imply that many will remain blinded even after He returns.
The key to understanding this section of scripture is helped by the term “in that day”. The term seems to normally denote the coming kingdom or millennial age. Some of the content here definitely implies the kingdom age.

The fountain that is opened after the Lord returns would imply that Jews (the house of David) will reside in Jerusalem as mortals. So, if this is true how can DANIEL BE TOLD that he will be resurrected at the end of the age which is understood by all as being the first resurrection (Dan.12-13)?. The answer seems obvious — following the resurrection not all will be saved. Otherwise the age has not yet ended when much of what is written here is being fulfilled for Israel.
Zechariah 13:3 And if anyone still prophesies, then his father and mother who gave birth to him will say to him, ‘You shall not live, for you have spoken falsely in the name of the Lord’; and his father and mother who gave birth to him will pierce him through when he prophesies.

So does this imply that death is still possible in the kingdom, for these spoken of are obviously mortals. Therefore these if residents of the kingdom can not be part of the bride (or of being immortal), nor are they eternal sons of God for whom there is no more death, because they still have earthly mothers and fathers, and they are still subject to death. Therefore they are either a part of the unsaved nation or nations who are to be ruled by Christ and His bride, or else they are still in theTribulation. These spoken of here are likely Jewish in nationality but not circumcised in heart. See Romans 2:28&29. So does this contradict Zechariah 13:1 above? No it actually causes it to make sense — why, think about it; if the resurrection brings Israel into immortality and perfection then a fountain to cleanse from sin and impurity is not necessary, unless there are still mortals present in the kingdom.
Zechariah 13:6 And one will say to him, ‘What are these wounds between your arms?’ Then he will say, ‘Those with which I was wounded in the house of my friends.’
This question obviously then comes from those who do not know Him, and so it is probably asked by those who are Judged by Him after His return, for the very reason that they do not yet know Him. It therefore is necessary in my openion that these would be Jews who were scattered among the nations, and who are now standing with those nations in judgment. Let’s see why I say this.
Zechariah 13:7 “Awake, O sword, against My Shepherd, And against the man, My Associate,” Declares the Lord of hosts. “Strike the Shepherd that the sheep may be scattered; And I will turn My hand against the little ones.
This verse regresses back to the time of Messiah’s rejection by Israel, and gives us our reason and understanding as to why we see the rejection of Jesus as the Messiah of Israel as being the cause of the Jewish dispersion throughout the nations.
Zechariah 13:8 “It will come about in all the land,” Declares the Lord, “That two parts in it will be cut off and perish; But the third will be left in it.
This would return us to Jews in Israel at the time of Tribulation or the time of Jacob’s trouble. The millennial kingdom will not begin until the return of the Lord during Armageddon to answer Israel’s calling out to Him (Hosea 5:15 & Isa. 63:1-6).  The Jews who are in Israel at this time will be put through the time of Jacobs trouble and will repent and seek the Lord.
Zechariah 13:9 “And I will bring the third part through the fire, Refine them as silver is refined, And test them as gold is tested. They will call on My name, And I will answer them; I will say, ‘They are My people,’ And they will say, ‘The Lord is my God.’”
This calling upon the lord would be the fulfillment of that prophesied by Hosea in 5:15, and by Jesus Himself in Matt. 23

Matthew 23:37-39 “Jerusalem, Jerusalem, who kills the prophets and stones those who are sent to her! How often I wanted to gather your children together, the way a hen gathers her chicks under her wings, and you were unwilling. Behold, your house is being left to you desolate! For I say to you, from now on you will not see Me until you say, ‘Blessed is He who comes in the name of the Lord!’”
And this promise or refinement of The Nation represents the physical saving of the nation Israel from the destruction of Armageddon as well as their inclusion into the new covenant. Thus they complete the bride, the bride has made herself ready (rev 19). And now finally “all Israel is saved” (Rom 11).
Zechariah 14:3 Then the Lord will go forth and fight against those nations, as when He fights on a day of battle.
This vs. is explained further in Isa. 63:1-7, and represents Jesus fighting for Israel after they repent and call for Him out of their distress (Hosea 5:15).
Zechariah 14:5 You will flee by the valley of My mountains, for the valley of the mountains will reach to Azel; yes, you will flee just as you fled before the earthquake in the days of Uzziah king of Judah. Then the Lord, my God, will come, and all the holy ones with Him!
In vs 4 the Lord prepares a way of escape for Israel, and in this verse He returns with His saints to rapture those remaining of His saints after they have fled in that escape.

This obviously again aludes to the action of the Lord represented in Isaiah 63, which occurs prior to His return to earth with His army of saints who have been given white robes in preparation for resurrection. 
Zechariah 14:6 In that day there will be no light; the luminaries will dwindle.
In that day — This is the same darkness as seen in Joel, in Isa, in Matt 24. The sun moon and stars will not shine in that day. And Paul also speaks of this darkness as he describes in 1Thess. 5:1-2 as a thief in the night. In order for Jesus to come for us in the night there must be darkness through out the entire earth.
Zechariah 14:12 Now this will be the plague with which the Lord will strike all the peoples who have gone to war against Jerusalem; their flesh will rot while they stand on their feet, and their eyes will rot in their sockets, and their tongue will rot in their mouth.
This is obviously explaining the battle of Armageddon itself.
Zechariah 14:16 Then it will come about that any who are left of all the nations that went against Jerusalem will go up from year to year to worship the King, the Lord of hosts, and to celebrate the Feast of Booths.
This is during the kingdom age after the Lords return and is one of several verses that allow us to see that mortals will enter into the kingdom to be ruled over by Messiah and His bride.
So can we honestly say that that day includes the Tribulation prophesied to come? — yes, but The Tribulation is not the day of the Lord. Remember it The Day of the Lord has specific definition. It occurs after Elijah’s coming, after the Sun, moon and stars are darkened, after the coming of Antichrist. That day which is spoken of here is the consummation of this current age leading to the kingdom age. And it could be nearer than we think.

I know that there is a great deal of information contained in this one article.  Please understand that i can’t possibly explain in great detail what it took me an entire book of 370 pages to explain.  but then you also need to study to show yourself approved just as I do.  God Bless as you study.