Revelation 4:6

And before the throne was a sea of glass like crystal: and in the midst of the throne, and within the circle of the throne, were four living beings full of eyes before and behind.

Revelation 5:6

And I beheld, and lo! in the midst of the throne, and of the four living beings, and in the midst of the presbyters, stood a lamb as just slaughtered, having seven horns and seven eyes, which are the seven spirits of God that are sent forth into all the world:

Revelation 15:2

And I saw as it were a sea of glass mingled with fire; and those who had obtained the victory over the beast, and over his image, and over his mark, and over the number of his name standing upon the sea of glass, holding the harps of God.

Revelation 7:11

And all the angels stood in a circle about the throne, and the presbyters and the four living beings, and fell on their faces before the throne, and worshipped God,

Revelation 14:3

and they sang as it were a new song before the throne, and before the four living beings, and the presbyters: and no person could learn that song, but the hundred forty-four thousand, who were redeemed from the earth.

Revelation 15:7

And one of the four living beings gave unto the seven angels seven golden vases full of the wrath of God, who liveth for ever and ever.

Revelation 19:4

And the four and twenty presbyters fell prostrate, and the four living beings, and they worshipped God who was seated on the throne, saying, Amen; Hallelujah.

Revelation 4:8-9

And the four living beings had each for himself six wings encircling him, and within they were full of eyes; and they never cease day and night, saying, Holy, holy, holy, Lord God Almighty, who was, and who is, and who is coming.

Revelation 5:14-1

And the four living beings said, Amen. And the four and twenty presbyters prostrated themselves, and worshipped him that liveth for ever and ever.

Revelation 7:17

Because the Lamb who is in the midst of the throne will feed them, as a shepherd, and lead them unto living fountains of waters; and God shall wipe away every tear from their eyes.

Revelation 21:11

having the glory of God: and her brilliance was like the most precious gem, as a jasper stone, transparent as crystal;

Revelation 21:18

The structure of the wall of it was jasper, and the city pure gold, like clear glass.

Revelation 21:21

And the twelve gates were twelve several pearls; every one of the gates was of one pearl; and the street of the city was pure gold, as transparent glass.

Revelation 22:1

AND he shewed me a clear river of water of life, bright as crystal, proceeding out of the throne of God and of 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 as it were a sea of glass mingled with fire; and those who had obtained the victory over the beast, and over his image, and over his mark, and over the number of his name standing upon the sea of glass, holding the harps of God.

Crystal

Revelation 21:11
having the glory of God: and her brilliance was like the most precious gem, as a jasper stone, transparent as crystal;
Revelation 22:1
AND he shewed me a clear river of water of life, bright as crystal, proceeding out of the throne of God and of the Lamb.

The midst

Revelation 5:6
And I beheld, and lo! in the midst of the throne, and of the four living beings, and in the midst of the presbyters, stood a lamb as just slaughtered, having seven horns and seven eyes, which are the seven spirits of God that are sent forth into all the world:
Revelation 7:17
Because the Lamb who is in the midst of the throne will feed them, as a shepherd, and lead them unto living fountains of waters; and God shall wipe away every tear from their eyes.

Four beasts

Revelation 4:8
And the four living beings had each for himself six wings encircling him, and within they were full of eyes; and they never cease day and night, saying, Holy, holy, holy, Lord God Almighty, who was, and who is, and who is coming.
Revelation 5:6
And I beheld, and lo! in the midst of the throne, and of the four living beings, and in the midst of the presbyters, stood a lamb as just slaughtered, having seven horns and seven eyes, which are the seven spirits of God that are sent forth into all the world:
Revelation 6:1
AND I saw when the lamb opened one of the seals, and I heard one of the four living beings, saying, as with a voice of thunder, Come, and see.
Revelation 7:11
And all the angels stood in a circle about the throne, and the presbyters and the four living beings, and fell on their faces before the throne, and worshipped God,
Revelation 14:3
and they sang as it were a new song before the throne, and before the four living beings, and the presbyters: and no person could learn that song, but the hundred forty-four thousand, who were redeemed from the earth.
Revelation 15:7
And one of the four living beings gave unto the seven angels seven golden vases full of the wrath of God, who liveth for ever and ever.
Revelation 19:4
And the four and twenty presbyters fell prostrate, and the four living beings, and they worshipped God who was seated on the throne, saying, Amen; Hallelujah.

Full

Revelation 4:8
And the four living beings had each for himself six wings encircling him, and within they were full of eyes; and they never cease day and night, saying, Holy, holy, holy, Lord God Almighty, who was, and who is, and who is coming.