Book of Zechariah 12:10-11.13:1.
Thus says the LORD:
I will pour out on the house of David
and on the inhabitants of Jerusalem
a spirit of grace and petition;
and they shall look on him whom they have pierced,
and they shall mourn for him as one mourns for an only son,
and they shall grieve over him as one grieves over a firstborn.
On that day the mourning in Jerusalem shall be as great as the mourning of Hadadrimmon in the plain of Megiddo.
On that day there shall be open to the house of David and to the inhabitants of Jerusalem, a fountain to purify from sin and uncleanness.