God has a plan, and he works all things out according to that plan. He hasn’t changed his mind from Eden to today. He is and always has been willing to pay the price to bring that plan into existence. The crucifixion is proof of that in that he takes responsibility for our errors, whether through ignorance or evil intent. Often we are willing to compromise our moral behavior to acquire or achieve something we value more. God is not. Some of us would unabashedly blame God, accusing him of monstrous behavior over his judgment of mankind during the days of the Genesis Flood, but would we be justified in our perception of him?
Assuming Bible chronology is true, there was about 1656 years separating the creation of mankind from coming of the flood. One must not put that figure in stone, because other genealogies mentioned in the Bible are rounded off, so let’s say that there may have been somewhere between 1656 and 2000 years between creation and the Flood, if the Bible is to be considered as a fairly accurate witness. How many people, therefore, would be living at the time of the Flood? After all, if we are speaking of 100 people, out of which God saved 8 people, we could hardly call it genocide. Could we? So, at what point does the word genocide fit God’s behavior in your opinion?
If we take into consideration, the long lifespan attributed to the people before the Flood, there could have been up to 40 billion people living on earth, if population rates grew then as they do today. Yet, this figure seems impossible without also attributing modern technology to that society, because after the population of the world grows to 1 billion, technology like refrigeration is needed to store food longer to keep the population from depleting through famine.
Since we have no evidence that ancient mankind was technologically advanced, we must assume the earth’s population was far less than a billion people. But, if this is so, how do we explain such an abbreviated population figure in the face of such longevity witnessed in Genesis 5 and following? According to the Biblical witness, childbearing was between 62 and 187 years, so it seems that marrying and raising families came a lot later than it does today. Moreover, Noah’s family at 500 years of age is only 3 sons, who by this time were married, but evidently had no families of their own. So, it doesn’t seem as though people had large families despite their longevity. In fact, some ancient texts tell us that the maturing process was a lot slower before the Flood. Notice:
“…a text listing kings of the city of Lagash… makes (it) clear that these ancients not only lived extraordinarily ‘long’ but also, apparently, lived extraordinarily ‘slowly,’ that took their time about growing up. The Lagash Kinglist says about the generations immediately after the flood had subsided: ‘In those days a child spent a hundred years in diapers… After he had grown up he spent a hundred years without being given any task (to perform)’”
Therefore, taking such things into consideration, and that according to the Bible there were only 10 generations (rounded off) from Adam to Noah, also taking into consideration Adam had at least one other line in Cain alongside the Seth line, what sort of population could we expect to exist at the time of the Genesis Flood?
I don’t pretend to be a mathematician, so I must accept the graphs and formulas etc. of those who are. I am told that, if we consider a literal understanding of the Adam and Eve story and apply to it the same rate of population growth from the creation of man to the Genesis Flood, as would need to be in place for us after the Flood to come to the great number of our own population today, then the population of the whole earth by the time of Genesis 6 and the Flood would be 41,415. If this figure is close to accurate for those destroyed in the Flood, then we need to take a good look at ourselves, before we judge God.
How many perished at Hiroshima and Nagasaki? Estimates range from 150-250 thousand, and these cities were chosen in order to kill the least amount of people and contain the destructiveness of the bombs. Many, perhaps most Americans, justify the bombings. It brought an early ending to World War II, and probably saved over a million lives on both sides had it been necessary to invade Japan via its beaches.
World War I deaths are estimated between 16 and 20 million, and this was called by many: the just war that would end all wars! Even if we were to double, triple or quadruple the calculation of the world’s population at the time of the Genesis Flood noted above, what God did doesn’t even approach what we consider acceptable casualties for a just war that would “end all wars.” I could go on, but what would be the point? Who are we to judge God, and that with as little information that could be conceivably drawn from the first six chapters of Genesis? How many of our neighbors have we killed over the centuries, all by ourselves? Don’t we more accurately fit the moral monster persona that we attribute to God?
 This figure is arrived at by adding the ages of the patriarchs at the age of their first born from Adam to Noah and adding that figure to Noah’s age at the time of the Flood.
 This is according to the KJV; according to the Septuagint, the figures are between 162 and 205 years.
 “I Studied Inscriptions from Before the Flood”: Ancient Near Eastern, Literary, and Linguistic Approaches to Genesis 1-11, page 134; Richard Hess and David Tsumura (eds.), Eisenbrauns: 1994.
 See World Population Prior to the Flood of Noah, by Art Porter: http://www.mybiblestudiesandcomments.com/world-population-prior-to-the-flood-of-noah.html
 From Wikipedia: http://en.wikipedia.org/wiki/World_War_I_casualties