UPDATE: There is another occurrence of a universal “all flesh” in vs. 19 which only adds to the strength of this argument.
I just finished translating Genesis 6. One of the things that stuck out to me was the repeated phrase “all flesh”. One of the many things I enjoy about translating Hebrew is that we are so familiar with the English text that we miss all sorts of details. But when we get into the Hebrew, everything pops out because you don’t skim over anything. Every dot and line (literally) needs to be considered when translating.
Among other things כָּל־בָּשָׂ֛ר (col basar, all flesh) is repeated three times in this chapter. The first use (Gen. 6:12) causes interpreters to waver between a literal understanding (“all flesh”) and figurative (“all people”). However the other two uses (Gen. 6:13, 17) is quite clearly literal since it refers to the end result of God’s plan, and the other is clarified to mean everything which has the breath of life under heaven. Having the breath of life is a trait shared by man and beast alike, and both are most certainly under heaven.
The question then is, is the first use limited compared to the other two? In other words, does the first use have a distinct meaning than the other two? Or do they all carry the same extensive meaning?
At this point I lean toward the latter since the only thing that clearly would limit the meaning in the first instance is the interpreter. There is no clear marker of specification that should cause us to limit the first use to only humans. How does an animal “corrupt their way”? Well, lets just say I consider a dog returning to its vomit corrupted (to cite one very minor example).
What’s the import? What difference does it make? It answers the question “why a global flood?”. If all flesh, man, animals, creeping things, and birds, were corrupted, it didn’t matter that man had not moved beyond the Mesopotamian area. It grieved God to his heart, but he decided in his wisdom that it was better to start [virtually] over and even in that demonstrate his infinite grace in allowing Noah and his sons, who had wicked hearts (Genesis 8:21) and all the animals, to survive and repopulate the earth.