The quarantine comes from the separation which exists between God and mankind: After Adam rebelled, Death entered the world. We are born separated form God. The story of the flood shows how much God hates our disobedience, but it also shows us that he prepares a way for him to rescue us.
Later, not covered in this story, he becomes a human being and sacrifices Himself so we can have everlasting life — if we accept it.
Celebration: