4 After this I looked, and there before me was a door standing open in heaven. And the voice I had first heard speaking to me like a trumpet said, "Come up here, and I will show you what must take place after this."  

door standing open in heaven. Jesus is the door (Lk 13:24) and all may come to God through him.

2 At once I was in the Spirit, and there before me was a throne in heaven with someone sitting on it.

someone sitting on it. God is sitting on the throne.

3 And the one who sat there had the appearance of jasper and carnelian. A rainbow, resembling an emerald, encircled the throne.

jasper and carnelian. These gems convey two important qualities of God: jasper—often stripped, so this speaks of the suffering of Christ; carnelian—fiery red which speaks of God’s anger. God anger is satisfied by the stripes of Jesus.   

4 Surrounding the throne were twenty-four other thrones, and seated on them were twenty-four elders. They were dressed in white and had crowns of gold on their heads.

twenty-four elders. Twenty four is the twelve sons of Israel and twelve apostles of the lamb. This group represents all believers.

dressed in white. We are righteous through the blood of Jesus (2 Cor 5:21).

crowns of gold on their heads. We have authority because Christ delegated power to us.

5 From the throne came flashes of lightning, rumblings and peals of thunder. Before the throne, seven lamps were blazing. These are the seven spirits a of God.

flashes of lightning, rumblings and peals of thunder. Description when the Law was given to Israel (Ex 19:16).

6 Also before the throne there was what looked like a sea of glass, clear as crystal.

In the center, around the throne, were four living creatures, and they were covered with eyes, in front and in back.

In the center, around the throne. Notice, all the elders are equal distance from the throne. Everyone in Christ is equal and has been given the same salvation and authority.

7 The first living creature was like a lion, the second was like an ox, the third had a face like a man, the fourth was like a flying eagle.

8 Each of the four living creatures had six wings and was covered with eyes all around, even under his wings. Day and night they never stop saying:

"Holy, holy, holy
is the Lord God Almighty,
who was, and is, and is to come."

four living creatures. Same description in Ezekiel, thus they are cherubim (Ez 10:20).

9 Whenever the living creatures give glory, honor and thanks to him who sits on the throne and who lives for ever and ever,

10 the twenty-four elders fall down before him who sits on the throne, and worship him who lives for ever and ever. They lay their crowns before the throne and say:

They lay their crowns before the throne. Though we reign on the earth, our dominion is derived from God.

11 "You are worthy, our Lord and God,

to receive glory and honor and power,

for you created all things,

and by your will they were created

and have their being."