At the end of the story of the Great Flood (which begins in Genesis 6:9), God declares that the rainbow is a sign of the covenant between God and the entire earth, that God will never again destroy the earth with a cataclysmic flood.
God said, “This is the sign of the covenant that I give between me and you and every living creature that is with you, from all generations forever. I have set my bow in the cloud, and it will be a sign of the covenant between me and the earth. When I bring clouds over the earth and the (rain)bow appears in the cloud. I will remember my covenant that is between me and you and every living creature among all flesh and there will never again be a flood to destroy all flesh.”
אֶת־קַשְׁתִּ֕י נָתַ֖תִּי בֶּֽעָנָ֑ן וְהָֽיְתָה֙ לְא֣וֹת בְּרִ֔ית בֵּינִ֖י וּבֵ֥ין הָאָֽרֶץ׃
I will set my bow in the cloud and it will be a sign of the covenant between me and the earth.
Rainbows, the spectrum of light visible in the sky, have captured the imagination of human beings around the world and been the subject of many myths in cultures around the world. In the ancient Near East, divine bows (as in bows and arrows) were often a symbol of warring gods. By contrast, in the Torah the bow becomes “a token of reconciliation between God and man” (The JPS Torah Commentary: Genesis). Traditional Jewish commentators mostly saw the rainbow as a natural phenomena that only gained its covenantal meaning after the flood, although its amazing appearance caused early Jewish sages to list it among ten supernatural items “created at twilight on the eve of the first Sabbath,” along with things like the manna and the staff of Moses (Pirke Avot 5:6).
Featured Image: Rainbow in Kauai, by Elisheva Danan