Revelation 4:6

And there was an ocean, as crystal-clear as glass, in front of the throne. And at the center, surrounding the throne were four living beings, covered with eyes in the front and back of them. [Note: In view of Isa. 6:1-3 and especially Eze. 10:20ff, these "living beings" appear to be some special order of heavenly beings who inhabit the presence of God].

Revelation 5:6

Then I saw a Lamb, looking like it had been killed. He was standing in the center of the throne, surrounded by the four living beings and the [twenty-four] elders. He has seven horns and seven eyes, which are the seven Spirits of God [i.e., the Holy Spirit. See 1:4], sent throughout the entire earth.

Revelation 15:2

And I saw what seemed to be an ocean of glass, mixed with fire, and those who had been victorious over the beast, his statue and the number of his name. They were standing beside [or, "on"] the ocean of glass and held harps [given to them] by God.

Revelation 15:2

And I saw what seemed to be an ocean of glass, mixed with fire, and those who had been victorious over the beast, his statue and the number of his name. They were standing beside [or, "on"] the ocean of glass and held harps [given to them] by God.

Revelation 7:11

And all the angels were standing around the throne and around the [twenty-four] elders and the four living beings. And they fell down on their faces in front of the throne and worshiped God,

Revelation 14:3

And they [i.e., the 144,000] were singing a new song in front of God's throne, and in front of the four living beings and the [twenty-four] elders. No one could learn [to sing] this song except the one hundred and forty-four thousand [See 7:4,9] who had been purchased from the earth.

Revelation 15:7

And one of the four living beings gave to the seven angels seven golden bowls filled with the wrath of God, who lives forever and ever.

Revelation 19:4

Then the twenty-four elders and the four living beings fell down and worshiped God, who sits on His throne. They said, "May it be so, Hallelujah!"

Revelation 19:4

Then the twenty-four elders and the four living beings fell down and worshiped God, who sits on His throne. They said, "May it be so, Hallelujah!"

Revelation 19:4

Then the twenty-four elders and the four living beings fell down and worshiped God, who sits on His throne. They said, "May it be so, Hallelujah!"

Revelation 19:4

Then the twenty-four elders and the four living beings fell down and worshiped God, who sits on His throne. They said, "May it be so, Hallelujah!"

Revelation 19:4-28

Then the twenty-four elders and the four living beings fell down and worshiped God, who sits on His throne. They said, "May it be so, Hallelujah!"

Revelation 19:4

Then the twenty-four elders and the four living beings fell down and worshiped God, who sits on His throne. They said, "May it be so, Hallelujah!"

Revelation 4:8-9

And each of the four living beings had six wings [and] were covered with eyes all around them and [even] within them. And day and night they never stop saying, [Note: Some translations have "singing" here and at other places below], "Holy, holy, holy [is] the Lord God Almighty, who was [in the past] and who is [in the present] and who will come [in the future]."

Revelation 5:14-1

And the four living beings said, "May it be so." And the elders fell down and worshiped.

Revelation 7:17

For the Lamb, who is at the center of the throne, will be their Shepherd and will lead them to springs of living water. And God will wipe away every tear from their eyes."

Revelation 21:11

It had the splendor of God [shining from it], and was as brilliant as a very precious stone, as crystal-clear as jasper.

Revelation 21:18

The material for the city's wall was jasper, and the city [itself] was made of pure gold, as clear as glass.

Revelation 21:21

And the twelve gates were made of twelve pearls, with each gate being made of a single pearl. And the street of the city was made of pure gold, as transparent as glass.

Revelation 22:1

Then the angel [See 21:9] showed me the river of the water of life. It was crystal-clear as it flowed out of the throne of God and the Lamb,

Treasury of Scripture Knowledge

Summary

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.

Bible References

A sea

Revelation 15:2
And I saw what seemed to be an ocean of glass, mixed with fire, and those who had been victorious over the beast, his statue and the number of his name. They were standing beside [or, "on"] the ocean of glass and held harps [given to them] by God.

Crystal

Revelation 21:11
It had the splendor of God [shining from it], and was as brilliant as a very precious stone, as crystal-clear as jasper.
Revelation 22:1
Then the angel [See 21:9] showed me the river of the water of life. It was crystal-clear as it flowed out of the throne of God and the Lamb,

The midst

Revelation 5:6
Then I saw a Lamb, looking like it had been killed. He was standing in the center of the throne, surrounded by the four living beings and the [twenty-four] elders. He has seven horns and seven eyes, which are the seven Spirits of God [i.e., the Holy Spirit. See 1:4], sent throughout the entire earth.
Revelation 7:17
For the Lamb, who is at the center of the throne, will be their Shepherd and will lead them to springs of living water. And God will wipe away every tear from their eyes."

Four beasts

Revelation 4:8
And each of the four living beings had six wings [and] were covered with eyes all around them and [even] within them. And day and night they never stop saying, [Note: Some translations have "singing" here and at other places below], "Holy, holy, holy [is] the Lord God Almighty, who was [in the past] and who is [in the present] and who will come [in the future]."
Revelation 5:6
Then I saw a Lamb, looking like it had been killed. He was standing in the center of the throne, surrounded by the four living beings and the [twenty-four] elders. He has seven horns and seven eyes, which are the seven Spirits of God [i.e., the Holy Spirit. See 1:4], sent throughout the entire earth.
Revelation 6:1
And I watched while the Lamb broke open one of the seven seals. Then I heard one of the four living beings saying in a thunderous voice [to the one on the white horse ?], "Come [out]."
Revelation 7:11
And all the angels were standing around the throne and around the [twenty-four] elders and the four living beings. And they fell down on their faces in front of the throne and worshiped God,
Revelation 14:3
And they [i.e., the 144,000] were singing a new song in front of God's throne, and in front of the four living beings and the [twenty-four] elders. No one could learn [to sing] this song except the one hundred and forty-four thousand [See 7:4,9] who had been purchased from the earth.
Revelation 15:7
And one of the four living beings gave to the seven angels seven golden bowls filled with the wrath of God, who lives forever and ever.
Revelation 19:4
Then the twenty-four elders and the four living beings fell down and worshiped God, who sits on His throne. They said, "May it be so, Hallelujah!"

Full

Revelation 4:8
And each of the four living beings had six wings [and] were covered with eyes all around them and [even] within them. And day and night they never stop saying, [Note: Some translations have "singing" here and at other places below], "Holy, holy, holy [is] the Lord God Almighty, who was [in the past] and who is [in the present] and who will come [in the future]."