Revelation 4

Revelation 4:3. "And there was a rainbow round about the throne, in sight like unto an emerald." The rainbow we know was appointed of God as a token of his gracious covenant with mankind. God is encompassed with a rainbow, which signifies that as he sits and reigns, and manifests himself in his church, he appears as encompassed with mercy. As of old, the throne of God in the holy of holies, where God manifested himself in the church of Israel, was called the mercy-seat, so here there is a rainbow, the sign of God's gracious covenant, round about the throne that he sits on. This rainbow was in sight like unto emerald, which is a precious stones of an exceedingly lovely green color; so green, that this color appears in nothing else so lively and lovely. This color is a most fit emblem of divine grace; it is a very lively color; not so dull as blue or purple, and yet most easy to the sight, more easy than the more fiery colors of yellow and red. It is the color of the grass, herbs, and trees, and all the growth of the earth, and therefore fitly denotes life, flourishing, prosperity, and happiness, which are often in Scripture compared to the green, flourishing growth of the earth. As the benign influence of the sun on the face of the earth is shown by this color above all others, so is the grace and benign influence and communication of God fitly represented by this color. This color is the color of joy and gladness. The fields are said to shout for joy, and also to sing, by their appearing in a cheerful green: as the color red is made use of to signify God's revenging justice, in Zechariah 1:8, and elsewhere; so is green the emblem of divine grace, as Dr. Doddridge observes: this does not imply that the rainbow had no other color, but that the proportion of green was greater than ordinary.