“…and there was a rainbow round about the throne, in sight like unto an emerald.” ~ Revelation 4:3
Note: the the emerald stone was the fourth stone in the breastplate of the High Priest and it represented the tribe of Judah, the one our Lord Jesus Christ came out of.
A similar vision is recorded in Ezekiel the first chapter when he saw the glory of the Lord above the “four living creatures” (who, by the way, represent a true ministry). In Ezekiel, he saw the throne of God riding above the four living creatures as follows:
“And there was a voice from the firmament that was over their heads, when they stood, and had let down their wings. And above the firmament that was over their heads was the likeness of a throne, as the appearance of a sapphire stone: and upon the likeness of the throne was the likeness as the appearance of a man above upon it. And I saw as the colour of amber, as the appearance of fire round about within it, from the appearance of his loins even upward, and from the appearance of his loins even downward, I saw as it were the appearance of fire, and it had brightness round about. As the appearance of the bow that is in the cloud in the day of rain, so was the appearance of the brightness round about. This was the appearance of the likeness of the glory of the LORD. And when I saw it, I fell upon my face, and I heard a voice of one that spake.” ~ Ezekiel 1:22-28
From the beginning the rainbow was a symbol given by God himself representing his promise of mercy:
“And God said, This is the token of the covenant which I make between me and you and every living creature that is with you, for perpetual generations: I do set my bow in the cloud, and it shall be for a token of a covenant between me and the earth. And it shall come to pass, when I bring a cloud over the earth, that the bow shall be seen in the cloud: And I will remember my covenant, which is between me and you and every living creature of all flesh; and the waters shall no more become a flood to destroy all flesh. And the bow shall be in the cloud; and I will look upon it, that I may remember the everlasting covenant between God and every living creature of all flesh that is upon the earth.” ~ Genesis 9:12-16
The reason there was a “rainbow round about the throne” is because God has always come with a cloud, and Jesus “cometh with clouds” (see Revelation 1:7), and clouds that are raining down are the ones that produce a rainbow. A rainbow from the viewpoint of the earth is like a half-circle, or a bow, but from above the cloud (if you have ever seen it in a cloud from a jet plane above the clouds) the bow is completely round. The Apostle John was spiritually “in the clouds” when he was in the spirit of worship, therefore he saw the throne of God in the clouds, and he saw a “round” rainbow rather than the typical one we see from the earth. “In the clouds” does not mean a physical cloud, but rather the “cloud of witnesses” (see Hebrews 12:1) made up of the people of God worshiping God! When people are in agreement from the heart, as the one church, worshiping God, there Jesus is right amongst them: “For where two or three are gathered together in my name, there am I in the midst of them.” (Matthew 18:20)
As also shown in this vision (see Revelation 4:5) when the “cloud of witnesses” gathers and God is there, there will be: lightning and thunder representing the judgement of God against all sin and false religion (including fake Christianity). And at the same time there will be the rainbow, showing that there is still mercy for those who will repent of sin and all false religion. A rainbow is produced when the light of the sun shines through the moisture or rain of a cloud – so the spiritual rainbow, (representing the promise of mercy to those who will fully repent of sin and allow Jesus to reign in their hearts) is produced when the light of the “Sun of Righteousness” (Malachi 4:2), who is Jesus, shines through.