A rainbow is reflective light creating an illusion of something that can be seen, and understood, but it is not really there. Not only is a rainbow a scientific phenomena that we simply just take for granted, God says a rainbow is a sign that He gave to Noah establishing a promise and relationship.
I am going to make a solemn promise to you and to everyone who will live after you. This includes the birds and the animals that came out of the boat. I promise every living creature that the earth and those living on it will never again be destroyed by a flood.
The rainbow that I have put in the sky will be my sign to you and to every living creature on earth. It will remind you that I will keep this promise forever. When I send clouds over the earth, and a rainbow appears in the sky, I will remember my promise to you and to all other living creatures. Never again will I let flood waters destroy all life. When I see the rainbow in the sky, I will always remember the promise that I have made to every living creature. The rainbow will be the sign of that solemn promise. Genesis 9:9-17
God desires people who want to be in relationship with Him and who recognize Him as Creator. God reveals Himself to His People as His People reflect God who can be seen in the world.
A rainbow consists of two major elements; light and water.
The word “light” shows up in the NKJ Bible 277 times. It says that light is revealing, and it is good.
And God saw the light, that it was good; and God divided the light from the darkness. Genesis 1:4
The Israelites were chosen to be a light to the nations to show them the way that God taught them:
Indeed He says, ‘It is too small a thing that You should be My Servant. To raise up the tribes of Jacob, And to restore the preserved ones of Israel; I will also give You as a light to the Gentiles, That You should be My salvation to the ends of the earth.’” Isaiah 49:6
Water is also an important element of God revealing more of His character. The Bible says water is cleansing, holiness, and salvation.
I will sprinkle clean water on you, and you shall be clean from all your uncleannesses, and from all your idols I will cleanse you. Ezekiel 36:25
With joy you will draw water from the wells of salvation. Isaiah 12:3
God gives us a rainbow to teach us something about who God is and who we are. God takes elements of this world, water and light, to reveal His glory in a multicoloured rainbow. In His purity and light he reveals a combination of colour that says, “here is God”, revel in His majesty, mystery, and awe.
Like the appearance of a rainbow in a cloud on a rainy day, so was the appearance of the brightness all around it. This was the appearance of the likeness of the glory of the Lord. Ezekiel 1:28
God’s People are also like a multicoloured rainbow; a reflection of God’s light who reveal the purest form of who God is. Water that cleans us outwardly and inwardly signifies our desires to be like God as we define our relationship with God purifying our souls. God is seen in each of us as we come together as one, all uniquely independently with God, but form in unity a spectrum of beauty. A marriage is established there that is a complete, unbroken, circle of strength. Knowing and understanding the relationship of love we have because of our Creator, reveals God’s magnificent beauty in the world.
All rainbows are full circles, however, the average observer only sees approximately the upper half of the arc, the illuminated droplets above the horizon from the observer’s line of sight. Entelki