In Genesis, God gave Noah a rainbow as the symbol of the covenant made after the flood.
Genesis 9 presents the covenant with Noah, his descendants, and every living creature. God promises that a flood will not again destroy all life on Earth, and the rainbow is described as the sign associated with that promise. The text places the sign in the clouds, connecting it directly with the flood narrative.
The covenant is broader than a private promise to Noah. It includes animals and future generations, making it a universal post-flood agreement within the story. The rainbow therefore functions as a visible reminder of the commitment.
The passage does not say that rainbows were created for the first time after the flood. Instead, it assigns a covenant meaning to the natural phenomenon. This distinction separates the biblical symbolism from later artistic or theological interpretations.