There's a concept that too the non-Christian can sound rather harsh, so be forwarned...
Assuming the Christian God exists as Christians describe Him. God is a perfect, God is creator. Now as the creation of God humans are His, completely. God hass total authority over us. He can choose to bless us or destroy us. We are like legos of his.
If I build a lego starship, but determin that it is flawed, or less then perfect, or if I just get board, I have every right to tear apart that creation of mine and start over.
In the same sense this creation is God's to do with as He pleases. Being perfect God has every right to demand perfection. And every right to destroy us if we are not perfect, or even every right to destroy uss even if we are perfect. We, along with the plants and animals are His property.
There is no such thing as fairness between us and God. God cannot be unfair to us. No more then I can be unfair to my legos.