Revelation 4:6

and before the throne there was as it were a sea of glass, like crystal. And in the center, around the throne, are four living creatures, full of eyes in front and behind.

Revelation 5:6

And between the throne and the four living creatures and among the elders, I saw a Lamb standing, as if it had been slain, with seven horns and with seven eyes, which are the seven spirits of God sent out into all the earth.

Revelation 15:2

And I saw what looked like a sea of glass mixed with fire and, standing beside the sea of glass, those who had been victorious over the beast and his image and over the number of his name. They held harps of God

Revelation 7:11

And all the angels were standing around the throne and around the elders and the four living creatures; and they fell on their faces before the throne and worshipped God,

Revelation 14:3

And they sang a new song before the throne and before the four living creatures and before the elders. No one could learn the song except the hundred and forty-four thousand who had been redeemed from the earth.

Revelation 15:7

Then one of the four living creatures gave to the seven angels seven golden bowls full of the wrath of God, who lives for ever and ever.

Revelation 19:4

And the twenty-four elders and the four living creatures fell down and worshipped God who is seated on the throne, saying, "Amen. Hallelujah!"

Revelation 4:8-9

And the four living creatures, each of them with six wings, are full of eyes all around and within, and day and night they never cease to sing, "Holy, holy, holy, is the Lord God Almighty, who was and is and is to come."

Revelation 5:14-1

And the four living creatures said, "Amen!" And the elders fell down and worshipped.

Revelation 7:17

For the Lamb in the center of the throne will be their shepherd, and he will guide them to springs of living water; and God will wipe away every tear from their eyes."

Revelation 21:11

having the glory of God, and its brilliance was like that of a very precious jewel, like a jasper, clear as crystal.

Revelation 21:18

The wall was made of jasper, and the city of pure gold, as clear as glass.

Revelation 21:21

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

Revelation 22:1

Then he showed me the river of the water of life, clear as crystal, flowing from 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 what looked like a sea of glass mixed with fire and, standing beside the sea of glass, those who had been victorious over the beast and his image and over the number of his name. They held harps of God

Crystal

Revelation 21:11
having the glory of God, and its brilliance was like that of a very precious jewel, like a jasper, clear as crystal.
Revelation 22:1
Then he showed me the river of the water of life, clear as crystal, flowing from the throne of God and of the Lamb,

The midst

Revelation 5:6
And between the throne and the four living creatures and among the elders, I saw a Lamb standing, as if it had been slain, with seven horns and with seven eyes, which are the seven spirits of God sent out into all the earth.
Revelation 7:17
For the Lamb in the center of the throne will be their shepherd, and he will guide them to springs of living water; and God will wipe away every tear from their eyes."

Four beasts

Revelation 4:8
And the four living creatures, each of them with six wings, are full of eyes all around and within, and day and night they never cease to sing, "Holy, holy, holy, is the Lord God Almighty, who was and is and is to come."
Revelation 5:6
And between the throne and the four living creatures and among the elders, I saw a Lamb standing, as if it had been slain, with seven horns and with seven eyes, which are the seven spirits of God sent out into all the earth.
Revelation 6:1
Then I saw when the Lamb opened one of the seven seals. And I heard one of the four living creatures say, as with a voice of thunder, "Come!"
Revelation 7:11
And all the angels were standing around the throne and around the elders and the four living creatures; and they fell on their faces before the throne and worshipped God,
Revelation 14:3
And they sang a new song before the throne and before the four living creatures and before the elders. No one could learn the song except the hundred and forty-four thousand who had been redeemed from the earth.
Revelation 15:7
Then one of the four living creatures gave to the seven angels seven golden bowls full of the wrath of God, who lives for ever and ever.
Revelation 19:4
And the twenty-four elders and the four living creatures fell down and worshipped God who is seated on the throne, saying, "Amen. Hallelujah!"

Full

Revelation 4:8
And the four living creatures, each of them with six wings, are full of eyes all around and within, and day and night they never cease to sing, "Holy, holy, holy, is the Lord God Almighty, who was and is and is to come."