Jerusalem, on Mount Zion, signifies the doctrine of love to the Lord, and how it governs your life. Jerusalem first comes to our attention in 2 Samuel 5, when King David takes the city from the Jebusites and makes it his capital. In the next chapter he brings the Ark of the Covenant there, and later it is where Solomon builds the temple, and his own palace. From then on Jerusalem is the center of worship of the Israelitish church. It is the place where the Lord was presented in the temple as a baby, where He tarried to talk to the priests at age twelve, where He cleansed the temple, had the last supper, was crucified and then rose. It is a central place in both the old and new Testaments. The city was built on Mount Zion, the highest point of the mountains of Judea. A city, in the Word, represents doctrine, the organized knowledge of the truths of the church. Mountains represent love of the Lord and the consequent worship. If you put those things together, Jerusalem on Mount Zion signifies the doctrine of love to the Lord, and how it governs your life. This is why David was led to make Jerusalem the most important city of the land, and why all worship was conducted there. And this is also why Jeroboam was condemned for introducing idol worship in Samaria. In the Book of Revelation, John's vision of the city New Jerusalem descending from God is a prophecy of a new dispensation of doctrine coming from the Lord.

(Verweise: Arcana Coelestia 4539, 8938; The Apocalypse Explained 365 [35-38])

469. He had in his hand a little book open. (10:2) This symbolizes the Word in respect to this point of doctrine there, that the Lord is God of heaven and earth, and that His humanity is Divine.

It may be seen in nos. 256, 259, and 295ff. above that the book which the Lamb took from Him who sat on the throne, the seals of which the Lamb loosed (Revelation 5:1, 7; 6:1ff.), means the Word. Consequently the little book in the hand of the angel, who also is the Lord (no. 465), means nothing else here than the Word in respect to some essential in it; and it is apparent from the particulars in this and the following chapter in the spiritual sense, and also from the natural sense in chapter 11, verses 15-17, that the essential is this point of doctrine in the Word, that the Lord is God of heaven and earth, and that His humanity is Divine.

[2] The little book is said to be open because this point of doctrine is plainly evident in the Word and is apparent to anyone who reads it, if he pays attention.

This is the subject now because it is the essential doctrine of the New Church. That is because everyone's salvation depends on a conception and acknowledgment of God. For the case is as stated in the Preface, that "heaven in its entirety is founded on a right idea of God, and so, too, the entire church on earth, and all religion in general," inasmuch as "that idea leads to conjunction, and through conjunction to light, wisdom, and eternal happiness."

[3] Now because the Lord is the one God of heaven and earth, therefore no one is admitted into heaven if he does not acknowledge Him, for heaven is the Lord's body. Instead the person remains below and is bitten by serpents, that is, by hellish spirits, from whose bite there is no cure but the one the children of Israel obtained by their looking at the bronze serpent (Numbers 21:1-9). That the bronze serpent means the Lord in respect to His Divine humanity is apparent from the following verses in John,

As Moses lifted up the serpent in the wilderness, so must the Son of Man be lifted up, that whoever believes in Him should not perish but have eternal life. (John 3:14-15)