Revelation 21:12,13

12Also she had a great and high wall with twelve gates, and twelve angels at the gates, and names written on them, which are the names of the twelve tribes of the children of Israel:

13 three gates on the east, three gates on the north, three gates on the south, and three gates on the west

A. The church is further described as having a high wall with 12 gates. There is a angel at each gate.

B. The 12 gates have the names of the 12 tribes of Israel written on them. There are three gates on each side of the holy city. You can approach the city (church) from any direction and find access.

C. The wall of a literal city was it primary defense against attack from the outside. If one is inside the wall, there is safety and protection. God has promised to protect those who are His. He offers security and safety to the church.

D. NOTE: This is not heaven. This city came down out of heaven. John is describing the church, the bride of Christ.