I'm glad you mentioned the third party for the concept of atonement. There are some in here that think we can atone for ourselves our sins. The very world suggests a third party. And, that the Lord said Isaac was his ONLY son. He wasn't. Does this mean that Father in Heaven has more than one child? Seems that way.
With Lot, Abraham bartered a bit with God getting the number down to 10 righteous persons before destroying the cities. Yet, Lot's family had less than 10 so the cities were destroyed. My take is that the wickedness was so bad that there was no ability for anyone to choose good or evil, which is a main point for us to be here. The City of Enoch was taken from the earth, not by destruction, but because the people had come to the point that they would not choose evil. Thus, no one would have the two choices. God removes those people from the earth. The method is based on if they are good or evil. And, Lot and his family were also wicked. The wife turned and looked at the cities burning and turned into a pillar of salt. The daughters raped their father after getting him drunk.