God has various employments for his holy angels. Sometimes they sound the trumpet of Divine Providence, and warn a careless world; sometimes they discover things of a heavenly nature of the heirs of salvation. Those who would have clear views of heaven, must get as near to heaven as they can, on the mount of meditation and faith. The subject of the vision is the church of God in a perfect, triumphant state, shining in its lustre; glorious in relation to Christ; which shows that the happiness of heaven consists in intercourse with God, and in conformity to him. The change of emblems from a bride to a city, shows that we are only to take general ideas from this description. The wall is for security. Heaven is a safe state; those who are there, are separated and secured from all evils and enemies. This city is vast; here is room for all the people of God. The foundation of the wall; the promise and power of God, and the purchase of Christ, are the strong foundations of the safety and happiness of the church. These foundations are set forth by twelve sorts of precious stones, denoting the variety and excellence of the doctrines of the gospel, or of the graces of the Holy Spirit, or the personal excellences of the Lord Jesus Christ. Heaven has gates; there is a free admission to all that are sanctified; they shall not find themselves shut out. These gates were all of pearls. Christ is the Pearl of great price, and he is our Way to God. The street of the city was pure gold, like transparent glass. The saints in heaven tread gold under foot. The saints are there at rest, yet it is not a state of sleep and idleness; they have communion, not only with God, but with one another. All these glories but faintly represent heaven.