V. The different impressions which that day will make upon the children of this world and the children of God, according as it will be to them. 1. To the wicked it will be a terrible day. The Lord shall then speak from Zion and Jerusalem, from the throne of his glory, from heaven, where he manifests himself in a peculiar manner, as sometimes he has done in the glorious high throne of his sanctuary, which yet was but a faint resemblance of the glory of that day. He shall speak from heaven, from the midst of his saints and angels (so some understand it), the holy society of which may be called Zion and Jerusalem; for, when we come to the heavenly Jerusalem, we come to the innumerable company of angels; see Heb. xii. 22, 25. Now is speaking in that day will be to the wicked as roaring, terrible as the roaring of a lion (for so the word signifies); he long kept silence, but now our God shall come, and shall not keep silence, Ps. l. 3, 21. Note, The judgment of the great day will make the ears of those to tingle that continue the implacable enemies of God's kingdom. God's voice will then shake terribly both heaven and earth (Isa. ii. 21), yet once more, Hag. ii. 6; Heb. xii. 26. This denotes that the voice of God will in the great day speak such terror to the wicked as were enough to put even heaven and earth into a consternation. When God comes to pull down and destroy his enemies, and make them all his footstool, though heaven and earth should stand up in defence of them and undertake their protection, it shall be all in vain. Even they shall shake before him and be an insufficient shelter to those whom he comforts forth to contend with. Note, As blessings out of Zion are the sweetest blessings, and enough to make heaven and earth sing, so terrors out of Zion are the sorest terrors, and enough to make heaven and earth shake. 2. To the righteous it will be a joyful day. When the heaven and earth shall tremble, and be dissolved and burnt up, then will the Lord be the hope of his people and the strength of the children of Israel (v. 16), and then shall Jerusalem be holy, v. 17. The saints are the Israel of God; they are his people; the church is his Jerusalem. They are in covenant and communion with him; now in the great day, (1.) Their longings shall be satisfied: The Lord will be the hope of his people. As he always was the founder and foundation of their hopes, so he then will be the crown of their hopes. He will be the harbour of his people (so the word is), their receptacle, refuge, and home. The saints in the great day shall arrive at the desired haven, shall put to shore after a stormy voyage; they shall go to be for ever at home with God, to their Father's house, the house not made with hands. (2.) Their happiness shall be confirmed. God will be in that day the strength of the children of Israel, enabling them to bid that day welcome and to bear up under the weight of its glories and joys. In this world, when the judgments of God are abroad, and sinners are falling under them, God is and will be the hope and strength of his people, the strength of their heart, and their portion, when other men's hearts fail them for fear. (3.) Their holiness shall be completed (v. 17): Then shall Jerusalem be holy, the holy city indeed; such shall the heavenly Jerusalem be, such the glorious church, without spot, or wrinkle, or any such thing. Jerusalem shall be holiness (so the word is); it shall be perfectly holy; there shall be no remainder of sin in it. The gospel-church is a holy society, even in its militant state, but will never be holiness itself till it comes to be triumphant. Then no stranger shall pass through her any more; there shall not enter into the New Jerusalem any thing that defiles or works iniquity; none shall be there but those who have a right to be there, none but its own citizens; for it shall be an unmixed society. (4.) God shall in all this be manifested and magnified: So shall you know that I am the Lord your God. By the sanctifying and glorifying of the church God will be known in his holiness and glory, as the God that dwells in his holy mountain and makes it holy by dwelling in it; and those that are sanctified and glorified are so through the knowledge of him that called them. The knowledge which true believers have of God is, [1.] An appropriating knowledge. They know that he is the Lord their God, yet not theirs only, but theirs in common with the whole church, that he is their God, but dwelling in Zion his holy mountain; for, though faith appropriates, it does not engross or monopolize the privileges of the covenant. [2.] It is an experimental knowledge. They shall find him their hope and strength in the worst of times, and so they shall know that he is the Lord their God. Those know best the goodness of God who have tasted and seen it, and have found him good to them.