John Gill Bible Commentary

For God will save Zion,.... The church of Christ, as it is often called; See Gill on Psa 2:6; this is to be understood not so much of the salvation of the people of God, by Christ, from sin and Satan, and the world, law, hell, and death, as of the preservation and continuance of the Gospel church state, notwithstanding all the opposition and persecution of the Jews and Gentiles; and especially of the deliverance of the Lord's people, in the latter day, from the cruelty, captivity, and bondage of antichrist, by the destruction of him; which will occasion joy and praise, Rev 18:4; and will build the cities of Judah: erect Gospel churches in the Roman empire, and in the several parts of the world; as were in the first times of the Gospel, and will be in the latter day, when the cities of God shall be yet spread abroad through prosperity, Zac 1:17; of which the saints are citizens, and enjoy in them many privileges and immunities: these may be said to be "built", when they are built upon Christ, and on their most holy faith; when the members of them are edified and multiplied; when purity of faith, discipline, and worship, prevails among them; and though this is usually by the ministers of the Gospel, as instruments, yet the Lord is the chief builder; for, unless he builds, in vain do the builders build, Psa 127:1; that they may dwell there, and have it in possession; the men of Judah, such as confess the name of Christ, as the word "Judah" signifies; who profess to believe in him with their hearts; these have a name and a place, and an inheritance in the churches, and an abiding one; they shall never go out, but dwell in the house of God for ever; Gospel churches being erected and built up for their sakes, and for such ends and purposes.