The Rainbow in Jewish Symbolism
The rainbow reminds Jews of God's glory and faithfulness to the covenant.
Reprinted from The Jewish Religion: A Companion, published by Oxford University Press.
After the Flood and the deliverance of Noah and his family, God shows Noah the rainbow in the clouds as a sign of His covenant with mankind that He will never again bring a deluge to destroy them (Genesis 9:8-17).
Nahmanides observes that the rainbow is a natural phenomenon, so that the narrative does not mean that God created the rainbow after the Flood, only that He declared that the already existing phenomenon would serve as the sign of His covenant from now on. The rainbow, pointing upwards, denotes, according to Nahmanides, that God's arrows would no longer shoot downwards to destroy the human race.
The Talmud (Berakhat 59a) states that a special benediction should be recited when beholding a rainbow. The exact form of this benediction is elaborated on and now appears in the Prayer Book as: 'Blessed art Thou, O Lord our God, King of the universe, Who remembers the covenant, is faithful to His Covenant, and keeps His word.'
The rainbow is mentioned again in the Bible in Ezekiel's vision of the Chariot: 'Like the appearance of the bow which shines in the clouds on a day of rain, such was the surrounding radiance. That was the appearance of the semblance of the Presence of the Lord. When I beheld it, I flung myself down on my face. And I heard a voice speaking (Ezekiel 1:29).'
To be noted is the circumspect manner in which the prophet describes his vision of the glory--'the appearance of the semblance.' Rashi, in a comment to verse 26, referring to the appearance of the glory, follows the Talmudic Rabbis: 'No permission has been given to reflect on the meaning of this verse.'
The Talmud (Hagigah 16a) states that one who gazes too intently at the rainbow will suffer a diminution of his eyesight. In the Kabbalah, the colors of the rainbow represent the various shades of the Sefirot. The rainbow has thus become in Jewish thought the symbol of both God's glory as manifest in the universe and God's faithfulness to His covenant to mankind and to the people of Israel.
The word berit ('covenant') is used both in connection with the rainbow and with circumcision, the covenant with Abraham.