In the Genesis story of Noah’s Ark, God set a rainbow in the clouds after the Flood. The rainbow serves as the sign of a covenant between God and Noah, his descendants, and every living creature.
Genesis presents the covenant as a promise that a flood would not again destroy all life on earth. The rainbow is therefore more than a weather detail: within the narrative, it is a visible reminder of the promise. The text connects the sign with clouds and with the future relationship between God and the earth.
The rainbow should not be confused with the dove that Noah sends from the Ark. The dove is part of Noah’s effort to learn whether the waters have receded. It returns with an olive leaf, while the rainbow appears later as the covenant sign.
Rainbows are optical phenomena produced when sunlight interacts with water droplets, but Genesis uses the familiar natural phenomenon symbolically. Similar covenant and flood themes appear in other ancient traditions, though the rainbow covenant is especially associated with the biblical account.