Revelation 4:1-3

After this I looked, and behold, a door standing open in heaven! And the first voice which I had heard, like the sound of a [war] trumpet speaking with me, said, “Come up here, and I will show you what must take place after these things.” At once I was in [special communication with] the Spirit; and behold, a throne stood in heaven, with One seated on the throne. [Ezek 1:26] And He who sat there appeared like [the crystalline sparkle of] a jasper stone and [the fiery redness of] a sardius stone, and encircling the throne there was a rainbow that looked like [the color of an] emerald. [Ezek 1:28; Rev 21:11, 19]