Revelation 4:3

³The one sitting on the throne was as brilliant as gemstones—like jasper and carnelian. And the glow of an emerald circled his throne like a rainbow.c

Revelation 4 opens the heavenly throne room vision that anchors the rest of the book. John is summoned through an open door in heaven and sees God seated on a throne, surrounded by twenty-four elders, four living creatures, and a sea of glass. The scene is one of unceasing worship,