Matthew Henry on Psalms 87:1-3

Christ himself is the Foundation of the church, which God has laid. Holiness is the strength and firmness of the church. Let us not be ashamed of the church of Christ in its meanest condition, nor of those that belong to it, since such glorious things are spoken of it. Other foundation can no man lay than that is laid, even Jesus Christ. The glorious things spoken of Zion by the Spirit, were all typical of Christ, and his work and offices; of the gospel church, its privileges and members; of heaven, its glory and perfect happiness.