Genesis places a rainbow in the sky as the sign of God’s covenant with Noah after the Flood.
In Genesis 9, God establishes a covenant with Noah, his descendants, and every living creature that survived the Flood. The rainbow is presented as the visible sign of that promise. Whenever it appears in the clouds, the text says, it recalls the covenant that the earth will not again be destroyed by a flood of that scope.
The rainbow therefore functions as more than a weather detail in the story. It is a memorial sign connecting the sky, the clouds, and the promise made after the waters recede. The covenant includes animals as well as people, a detail sometimes left out of simplified retellings.
Genesis does not describe the rainbow as something Noah carries from the Ark. It appears after the survivors leave the vessel and after the covenant is announced. In later Jewish and Christian interpretation, the rainbow remains strongly associated with hope, mercy, and divine promise.