The rainbow is also a mystical symbol. The prophet Ezekiel, in exile in Babylonia (6th Century BCE), had an ecstatic vision of God and compared the brightness of this vision to the appearance of a rainbow.
Ezekiel’s vision lead to the association of the rainbow with the divine glory, the immanence of God. According to the Zohar, a mystical commentary on the Torah, the rainbow is identified with the Shechinah, the indwelling, feminine divine presence. She shared her rainbow colored garment with Moses when he ascended Mount Sinai and the cloud covered the mountain (Exodus 24:15). The seven colors of the rainbow reflect the seven lower sefirot (divine emanations/energies/qualities) through which the God interfaces with creation. So whenever we see a rainbow we are reminded of Divine glory.
As the appearance of the bow that is in the cloud in the day of rain, so was the appearance of the brightness round about. This was the appearance of the likeness of the glory of YHWH. I saw it and I fell face down, and I heard a voice speaking.–Ezekiel 1:28
כְּמַרְאֵה הַקֶּשֶׁת אֲשֶׁר יִהְיֶה בֶעָנָן בְּיוֹם הַגֶּשֶׁם כֵּן מַרְאֵה הַנֹּגַהּ סָבִיב הוּא מַרְאֵה דְּמוּת כְּבוֹד יְהוָה וָאֶרְאֶה וָאֶפֹּל
Featured Image: Rainbow in Feather Falls, California, JHD