Jesus Is Fully God and Not Man

Nestorianism is saying that Jesus is just a man and then Euchuchus or Euchachianism says that Jesus is fully God but not man at all. And the difference between these two is profound. If you've ever wondered why the Trinity mattered, why does it matter that Jesus is both God and man? It all revolves around our salvation because if Jesus was not who he claimed to be, we have no hope. He can't defeat death if he's purely man and not God. Then he can't be our substitute if he's fully God and not man. So there's consequences to either side.