In Genesis, a rainbow is the sign of God’s covenant after the Flood.
Genesis 9 describes a covenant made with Noah, his descendants, and every living creature after the waters recede. God sets the rainbow in the clouds as a sign of the promise never again to destroy all life with a flood. The passage connects the visible arc with remembrance of the covenant.
This covenant follows Noah’s emergence from the ark and the offering he makes after reaching dry land. It is broader than a promise to Noah’s immediate family: the text repeatedly includes future generations and the animals of the earth.
The rainbow is therefore presented in Genesis as a covenant sign, not as the cause of the Flood or as a navigational marker. In later Jewish, Christian, and popular culture, it became an especially familiar image of hope, peace, and divine promise, although those broader meanings extend beyond the specific biblical wording.