1 After this I looked, and, behold, a door was opened in heaven: and the first voice which I heard was as it were of a trumpet talking with me; which said, “Come up hither, and I will show thee things which must be hereafter.”
After John was given the messages to the churches- and maybe after he wrote them down and sent them- he saw a door open up in the sky and heard a trumpet calling him to heaven to see the future.
2 And immediately I was in the spirit: and, behold, a throne was set in heaven, and One sat on the throne.
John was no longer conscious of his physical body. Whether he was physically taken into heaven or simply given a vision, we can’t really tell.
A throne is a place of authority and judgment.
3 And He that sat was to look upon like a jasper and a sardine stone: and there was a rainbow round about the throne, in sight like unto an emerald.
The one sitting on the throne was as beautiful as Jasper stones (transparent with rays of color) and as a Sardis stone (red and a symbol of judgment).
The rainbow is the symbol of God’s promise to us that He won’t ever flood the earth again. Here it represents all of His promises to us. It is colored like an emerald; green like refreshing new life.
4 And round about the throne were four and twenty seats: and upon the seats I saw four and twenty elders sitting, clothed in white raiment; and they had on their heads crowns of gold.
Twelve seats for the patriarchs of the Old Testament (representing the 12 tribes of Israel), and twelve for the Apostles of the New Testament. This symbolizes the Bible and all who believe it, both before the Cross and after. They are clothed in purity, are close to God, and have authority on their heads; the authority that comes from God’s word.
5 And out of the throne proceeded lightenings and thunderings and voices: and there were seven lamps of fire burning before the throne, which are the seven Spirits of God.
Seven is the number of completeness in the Bible. The entirety of God (who is not confined by math as we are) is there at the throne, functioning and serving God’s ultimate purpose.
6 And before the throne there was a sea of glass like unto crystal: and in the midst of the throne, and round about the throne, were four beasts full of eyes before and behind.
In front of both the tabernacle in the wilderness and the temple in Jerusalem was a large, brass basin, called a "sea," used for the cleansing of the priests before they ministered. Here is a “sea” before the throne for the cleansing of the saints purer than water; as pure as a sea of glass and crystal.
John sees four animals. Because of their closeness to the throne (between God and the twenty-four) and their characteristics, we can assume they are the ministry. The ministry must be very watchful as they are responsible for the souls of all entrusted to them.
(These beasts bear a resemblance to the beasts of Ezekiel, but I do not believe they are the same. The ones in Ezekiel appear to be representing God Himself, while these beasts are praising God, not representing Him.
The word “Christian” means “Christ-like,” so it would be natural for those who serve God to develop similar characteristics and be described with similar imagery.)
7 And the first beast was like a lion, and the second beast like a calf, and the third beast had a face as a man, and the fourth beast was like a flying eagle.
Ministers must have the courage of a lion, work like an ox (calf), be as wise and insightful as a man compared to animals, and have their minds on heavenly things like an eagle.
8 And the four beasts had each of them six wings about him; and they were full of eyes within--
The eyes of the beast looked within as well as without. Ministers must be especially careful that they don’t fall from God. They must be constantly watching for their own spiritual health as well as that of those around them.
-- And they rest not day and night, saying, “Holy, holy, holy, Lord God Almighty, which was, and is, and is to come.”
The beasts were always praising God and pointing out who He is. Ministers must always be showing God to the world and identifying His every aspect.
9 And when those beasts give glory and honor and thanks to Him that sat on the throne, who liveth for ever and ever,
10 The four and twenty elders fall down before Him that sat on the throne, and worship Him that liveth for ever and ever, and cast their crowns before the throne, saying,
When the ministry does its job, the saints will worship God.
The twenty-four threw their crowns, their symbols of authority, down in front of God, acknowledging that He is the Ultimate Power.
11 “Thou art worthy, O Lord, to receive glory and honor and power: for thou hast created all things, and for thy pleasure they are and were created.”
The Church is bringing the glory to God that He deserves and acknowledging that He is the creator of all things. He made the universe and everything in it (right down to the tiniest flower), because He wanted to. This whole creation was made for the ultimate purpose of pleasing God.