What rainbow-related promise did God make after Noah's Ark came to rest?

After Noah's Ark came to rest, God promised never again to destroy the Earth by flood.

In Genesis 9, God establishes a covenant with Noah, his descendants, and every living creature that survived the Flood. The rainbow is presented as the sign of that covenant. The promise is specifically about a catastrophic flood destroying all life; it is not a promise that rain or ordinary floods will never occur again.

The covenant passage expands the story beyond Noah's personal survival. It includes animals and future generations, making the rainbow a recurring reminder of the agreement. The text also connects the sign with God's remembrance of the covenant whenever the rainbow appears in the clouds. Modern uses of the rainbow as a symbol may carry additional meanings, but Genesis gives this particular theological explanation for its role after the Flood.