Matthew Henry Commentary Zechariah 12:9-14

"And it shall come to pass in that day, that I will seek to destroy all the nations that come against Jerusalem. And I will pour upon the house of David, and upon the inhabitants of Jerusalem, the spirit of grace and of supplication; and they shall look unto 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 first-born. In that day shall there be a great mourning in Jerusalem, as the mourning of Hadadrimmon in the valley of Megiddon. And the land shall mourn, every family apart; the family of the house of David apart, and their wives apart; the family of the house of Nathan apart, and their wives apart; the family of the house of Levi apart, and their wives apart; the family of the Shimeites apart, and their wives apart; all the families that remain, every family apart, and their wives apart." — Zechariah 12:9-14 (ASV)

The day spoken of here is the day of Jerusalem's defense and deliverance, that glorious day when God will appear for the salvation of his people. In Christ's first coming he bruised the serpent's head and broke all the powers of darkness that fought against God's kingdom among men. In his second coming he will complete their destruction, when he shall put down all opposing rule, principality, and power; and death itself shall be swallowed up in that victory.

The Holy Spirit is gracious and merciful, and is the Author of all grace or holiness. He is also the Spirit of supplications, and shows men their ignorance, need, guilt, misery, and danger. At the time foretold here, the Jews will know who the crucified Jesus was; then they will look by faith to him, and mourn with the deepest sorrow, not only in public, but in private, even each one separately. There is a holy mourning, the effect of the pouring out of the Spirit; a mourning for sin, which enlivens faith in Christ and qualifies for joy in God.

This mourning is a fruit of the Spirit of grace, a proof of a work of grace in the soul, and of the Spirit of supplications. It is fulfilled in all who sorrow for sin in a godly manner; they look to Christ crucified and mourn for him. Looking by faith upon the cross of Christ will cause us to mourn for sin in a godly manner.