Sea Breeze: What if someone chooses a purpose that requires them to murder you?
You seem to be saying that, without God, we cannot agree on standards of behavior. Yet human societies have managed this for thousands of years, and do so to this day. Do you believe that, without God, we would not be able to determine why murder is bad?
As for God's character, we are referring to a being who defines itself as jealous, angry, vengeful, and a god of armies. Who wiped out almost all life on the planet with a flood. Who led his chosen people through a violent scouring of cities and cultures that occasionally involved the killing of every last man, woman, and child, and sometimes even livestock. Who struck dead a man who reached out to steady the ark of the covenant, when he feared it might fall.
An individual who decides that his purpose requires my murder is scary, but I can have hope that I may avoid or overcome him. An all-powerful God who can wipe out whole populations with a thought, and has demonstrated that capability before? That is terrifying.