And the LORD said, My spirit shall not always strive with man, for that he also is flesh: yet his days shall be an hundred and twenty years. (Gen 6:3 KJV)
There are two ways of interpreting this. The lifespan of a person is one hundred twenty years, or in one hundred twenty years, I will send a flood.
The problem with the first interpretation is that no one lives one hundred twenty years, not then, not now and not in between.
So, I interpret this to indicate when the flood will come after God said, ‘Enough, already!’ (Literally: his days will be one hundred twenty years)
Trinity: