Bible Verses About The Sea: (Smooth as glass,) of the peace of heaven

In front of the throne was what looked like a sea of glass, clear as crystal. In the center, around the throne, were four living beings covered with eyes in front and behind.

I saw what looked like a sea of glass mixed with fire. Those defeating the beast, its image and the number of its name were standing by the sea of glass, holding harps which God had given them.