The Rainbow in Genesis

I am reading a chapter in Sacred Bond about the Noahic covenant. The Noahic covenant is a covenant of common grace. God's makes promises to all men and all flesh. The rainbow is the sign God gives us that he remembers those promises. The authors spent some time on rainbows what it symbolizes to the ancient world and what it should symbolize to us today.

So what does the rainbow symbolize? There are two scholarly interpretations of the rainbow, both of which are worthy of mention. First, the Hebrew word for rainbow can mean either rainbow or bow, as in bow and arrow. God calls it "my bow" in verse 13. In ancient iconography, victorious kings and gods are pictured coming back from war with their bows in a horizontal position (like a rainbow). Going into battle, the king/god has the bow vertical in hand, ready to shoot; but after battle it is horizontal, symbolizing the peace after war. The rainbow, then, could be symbolic of God's war bow that hangs in the sky, symbolic of peace. God will not destroy the world again; he is no longer hostile.

Second, the ancients understood the sky or firmament as a dome-shaped barrier that held back the waters above, as in Genesis 1:6-7. Hence, when God judged the world in the flood, he opened the windows of heaven, releasing the waters above (7:11). In fact, the Hebrew word for flood refers more specifically to these celestial waters. Thus, God's promise is that he will never wipe out all flesh by the waters of the flood. The rainbow then visually represents the dome-shaped firmament as shut. The rainbow appears when it rains to show that the celestial waters will not be released.

The symbolic value of the rainbow could be either of these, or perhaps both. Either way, the effect of the symbol is clear. The rainbow reminds us that the floods will never come again. The beautiful arch points to God's promise that he will never judge the world by the waters of the flood. The firmament is shut; there is peace after the storm. (pp. 76-77, Sacred Bond: Covenant Theology Explored by Michael G. Brown and Zach Keele)