Zechariah 11 and 13 refer to Jerusalem at the time of Judas' betrayal of Christ (11:12-17,) and Christ's crucifixion (12:10-14.) Chapter 13 begins with the Day of Pentecost (13:1.) But it also refers to one of the fulfilments that Jesus mentioned (13:7) :
This is Judas (Mat 26:15, 27:3-5)
"And I said unto them, If ye think good, give me my price; and if not, forbear. So they weighed for my price thirty pieces of silver. And the Lord said unto me, Cast it unto the potter: a goodly price that I was prised at of them. And I took the thirty pieces of silver, and cast them to the potter in the house of the Lord." (Zec 11:12-13 KJV)
This is Christ on the Cross (John 19:32-37)
"And I will pour upon the house of David, and upon the inhabitants of Jerusalem, the spirit of grace and of supplications: and they shall look upon me whom they have pierced, and they shall mourn for him, as one mourneth for his only son, and shall be in bitterness for him, as one that is in bitterness for his firstborn." (Zec 12:10 KJV)
The day of Pentecost:
"In that day there shall be a fountain opened to the house of David and to the inhabitants of Jerusalem for sin and for uncleanness." (Zec 13:1 KJV)
Smite the Shepherd (Mat 26:31: )
"Awake, O sword, against my shepherd, and against the man that is my fellow, saith the Lord of hosts: smite the shepherd, and the sheep shall be scattered: and I will turn mine hand upon the little ones." (Zec 13:7 KJV)
Those items cannot be ignored in interpreting "the siege both against Judah and against Jerusalem" in 12:2 and the "burdensome stone" in 12:3.
What is the "burdensome stone," anyway? Jesus is mentioned as a type of stumblingstone many times, and also in his prophetic role as the Branch:
Isa 8:13-15, 28:14-18; Zec 3:8-9; Rom 9:30-33; 1 Pet 2:4-10
Philip