אֶת־קַשְׁתִּ֕י נָתַ֖תִּי בֶּֽעָנָ֑ן וְהָֽיְתָה֙ לְא֣וֹת בְּרִ֔ית בֵּינִ֖י וּבֵ֥ין הָאָֽרֶץ׃
I have set My bow in the cloud, and it shall be for a token of a covenant between Me and the earth.
Read kabbalistic (mystical) interpretation of Genesis 9:13: and classical mystical sources.