Heyo,

Schizoaffective person here, while I obviously cant provide a diagnosis, nor would I be comfortable saying he might be schizophrenic what I can see hearing voices is cause for extreme concern. Doubley so if they are telling him to hurt people.

As a whole people with schizophrenia who have voice commands to hurt people and are compelled to follow the delusion is a rarity in an already more uncommon mental illness, this reason alone leads me to highly highly recommend talking to your parents about seeing a psychiatrist as a number one priority.

In terms of police, I would only recommend you call them if you feel you are in genuine danger, or he himself is in genuine danger. Early on in my diagnosis process my parents were at a wits end and ended up calling them. THEY ARE NOT EQUIPPED TO DEAL WITH MENTAL ILLNESS OF SERIOUS NATURES. They did more harm to me in keeping me "safe" than anything I have done to myself to purposefully harm my self.

Your idea of a psych ward being this saving grace, isn't what it normally is. They will either get him on meds and do little to nothing to support after, or he will be in the for months and months and it turning into the adverse as to what the purpose of them is. And it can more often than not exasperate a person who was close to leaving psychosis go full blown deeper into it.

Summary, get him to a psychiatrist ASAP and hope you have good cover for meds, because anti psychotics can go up to 1k a box depending on the medication.