Over 121 years had passed since Noah had heard God say: "Everything... shall perish... but I will establish My covenant with you" (Genesis 6:17-18).
The first part— that everything would perish— had already been fulfilled. Everything really had perished! In fact, the entire earth— everything with the breath of life— had drowned in God's judgment.
The second part— that God would establish His covenant— had not yet been fulfilled. Whether Noah, over those 121 years, thought often about the coming covenant that would eventually be established is hard to tell. Yet when God finally did establish His covenant with Noah, Noah's mind must have raced back to that distant memory when God had first spoken of it.
When God made His covenant with Noah, He not only spoke to Noah, but also to Noah's sons. In doing this, God made it clear that the covenant did not merely apply to Noah, but to all of his descendants— to everyone living on the earth, from the flood to this very day.
Then God spoke to Noah and to his sons with him, saying, "Now behold, I Myself do establish My covenant with you, and with your descendants after you; and with every living creature that is with you, the birds, the cattle, and every beast of the earth with you; of all that comes out of the ark, even every beast of the earth. I establish My covenant with you; and all flesh shall never again be cut off by the water of the flood, neither shall there again be a flood to destroy the earth." (Genesis 9:8-11)Stop for a moment. Think. Think deeply about this simple fact: God made a covenant with man.
God. The eternal one. The always present One. God who is all powerful, who is all knowing. God who is without the stain of sin. God who is spotless, unblemished. And above all, God who is holy, holy, holy...
That holy God made a covenant with man. Such an event would have been spectacular enough even if man had not been in a fallen state— but man is in a fallen state. God did not merely make a covenant with man, but He made a covenant with fallen man. Think about that! God made a promise to fallen man.
The God of all truth made a promise to sin-loving people who twist the truth and break their promises! He promised that He would never again send an all-consuming flood. Never again would He use a flood to destroy all flesh!
What Is The Noahic Covenant? - Genesis 9:12-17
God's Covenant With Noah: Promised - Genesis 6:18
The Coming Flood of the Pre-Flood World - Genesis 6:17
The Origin Of The Death Penalty - Genesis 9:5-7
Noah's Name: Its Meaning and Significance - Genesis 5:29