Emerging from the arc into the freshly washed creation, God speaks to Noah and his family. His speech intentionally reminds us of the blessing way back in 1;28-. It is nearly a fresh start for creation, albeit with some very important differences:
Noah emerges and immediately offers a sacrifice. (This is the first time we explicitly see a sacrifice. Cain and Abel’s offerings are not so graphically described.) This is an enormous difference between Noah and Adam. Adam began in a relationship with the Creator and turned his back. Noah also has a relationship, but hindered by sin. God has approached and saved Noah, and in gratitude Noah offers a sacrifice. However, there is more here than mere gratitude. Humanity is separated from God by sin and the only way we can catch a glimpse of the relationship we should have with God is through sacrifice. We see here that the “aroma” of the burnt offering helps God accept mankind and decide to never destroy creation like He had in the flood.
Noah is commanded (like Adam and Eve) to be fruitful and fill the earth. Before humanity had filled the earth with violence. Before we started with a couple who had just decided that they could do better than God. There is an unspoken hope in the text that this time things might be better. Noah was born and named, after all, with the hope that he might bring humanity rest from the curse. We know that that is not the way things will go. That said, we are now starting with a family that wants to please God. All those good intentions are not enough to overcome the curse humanity has brought upon itself. But God has stepped in and shown grace in the midst of judgement.
This time around, God adds some additional information into the multiplication command. Before man was to manage creation and rule over the animals. Now the animals will fear man and he can eat them. Before man’s sin led to murder and violent revenge. The whole earth became overrun with violence. Now God commands that murder will carry an appropriate judgement. But it will not be revenge. Society will judge one the issue of guilt and carry out the punishment.
The pinnacle of this moment in history is the promise from God to creation that He will never again issue this sort of destruction. He takes as a symbol and reminder of this promise the rainbow. This is not the creation of the rainbow. God tends to use existing things and practices as reminders for us. (See later how He applies special, covenantal meaning to circumcision and baptism.) But it is a reminder that we should see in rainbows a reminder of God’s grace in our lives. Not on an “ordinance” level, perhaps, but it is something that should trigger a thought every time we see one.