God’s rainbow has seven colors - the Hebrew word “rainbow” - (qesheth) also has seven letters. Seven is God's number for perfection.
8God spoke as follows to Noah and his sons,
9 'I am now establishing my covenant with you and with your descendants to come,
10 and with every living creature that was with you: birds, cattle and every wild animal with you; everything that came out of the ark, every living thing on earth.
11 And I shall maintain my covenant with you: that never again shall all living things be destroyed by the waters of a flood, nor shall there ever again be a flood to devastate the earth.'
12 'And this', God said, 'is the sign of the covenant which I now make between myself and you and every living creature with you for all ages to come:
13 I now set my bow in the clouds and it will be the sign of the covenant between me and the earth.
14 When I gather the clouds over the earth and the bow appears in the clouds,
15 I shall recall the covenant between myself and you and every living creature, in a word all living things, and never again will the waters become a flood to destroy all living things.
16 When the bow is in the clouds I shall see it and call to mind the eternal covenant between God and every living creature on earth, that is, all living things.'
17 'That', God told Noah, 'is the sign of the covenant I have established between myself and all living things on earth.
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The next time you see a Rainbow, give praise to God the maker of all creation.