The Bible is rather contradictory on this point. God punishes Cain for killing Abel. And god does command, thou shalt not kill. But god kills a whole number of first born Egyptians himself. And he orders his people to kill rape victims, whole cities just for being on land he wants for his people. God seems rather more ambivalent about killing than I am.
If there is a god, I want to believe that there is a god. If there is not a god, I want to believe that there is no god.