“I have placed my rainbow in the clouds. It is the sign of my covenant with you and with all the earth” (Genesis 9:13 NLT).

The Noahic (Rainbow) Covenant
 
Whether this was the first appearance of a rainbow or not, the rainbow was now a sign of God’s covenant with Noah and “all the earth.” (Some speculate that it was the first rainbow because the post-flood atmosphere of the earth was changed from its pre-flood condition – This is called the “canopy theory.” ) This covenant had three important features:
1) It’s an unconditional covenant. This covenant is based on God’s faithfulness, not man’s (Gen. 9:9).
2) It’s a universal covenant. It’s for “all the earth.” No one is excluded.
3) It’s an everlasting covenant. God said, “Never again will a flood destroy the earth” (Gen. 9:11).
 
The covenant God made with Noah and “all the earth” is still active today. The next time you see a rainbow, think of God’s faithfulness.