In the Bible, a rainbow symbolizes God's promise to mankind never to send another great flood to destroy the world. The rainbow appears to Noah and his family in the book of Genesis after the flood's destruction of the wicked inhabitants of the Earth.
Rainbows also appear in the books of Exodus and Revelation as symbols of the glory of God. In Exodus, the prophet Ezekiel has a vision from God of a wheel within a wheel, which he compares to the brightness of a rainbow. In Revelation, the apostle John has a vision of God enthroned in glory, and he describes the throne as being surrounded by a rainbow.