Congratulations
, you answered your own question; it is indeed a paradox. And it is a paradox because God had nothing to do with it. It was our own ill-informed decision all along. It is like the story of the Prodigal Son. This universe is/was an ill-informed choice to seemingly leave home (God, Oneness) and try to dualistically live separate from our source, which is in truth possible only in fictitious dreams. And that is what Christianity would be all about if people didn’t love the old testament so much. The more we try to justify this world and make it real, the more paradoxical it all becomes. There are plenty of paradoxes in the sciences just as there are in religions. Paradoxes are a sign of a bad or incomplete theory.