What will happen to the house of David when they see the coming manifestation of the Messiah?
When the house of David sees the coming manifestation of the Messiah, God will pour upon them the spirit of grace and supplications. Their spiritual eyes will be opened, and they will recognize Him as the One they pierced—the Messiah who died on the Roman cross.
Les explains that Zechariah 12:10 addresses specifically the house of David and the inhabitants of Jerusalem, not Gentiles. When they see the coming manifestation of the Christ, their physical eyes will be opened and their spiritual eyes will be opened, so they recognize that this coming manifestation of the Messiah is the One who was pierced—the One who died on the Roman cross. God will pour upon them the spirit of grace and supplications. Also, Zechariah 13:6 refers to wounds in His hands, wounded in the house of His friends. This remnant of Israel will experience the new birth that Nicodemus was told he had to have to enter the kingdom.
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.