According to Genesis, God set a rainbow in the clouds as the sign of the covenant with Noah.
After Noah left the Ark, Genesis describes God making a covenant with Noah, his descendants, and every living creature. The rainbow appears in the clouds as a reminder of that promise. The covenant states that waters would not again become a flood destroying all life on Earth.
The rainbow is therefore presented in the text as a covenant sign, not as an object Noah carried or built. The account connects the sign with clouds and rain, linking a visible natural phenomenon to the story’s theological promise. Biblical passages elsewhere also use rainbows in symbolic visions, but Genesis 9 is the passage specifically associated with Noah’s covenant after the Flood.