His brother called for help and their father approached 19-year-old Rawson to try and calm him down.
The teen picked up a large branch from beside the fireplace and swung it at his father, saying he would kill him.
Rawson's father avoided the blow, but a second and third hit his shoulder.
His stepmother told Rawson to leave his father alone as she entered the room.
Rawson struck her multiple times with the branch.
He then picked up a pair of scissors and stabbed her in the hip.
He pulled her hair and tried to stab her in the temple, but instead the blows reached her left cheek, her ear, and the finger webbing of her left hand she raised to defend herself.
She broke free and left the room.
In a police interview, Rawson said he had disliked his stepmother for a long time and wanted to kill her with the scissors.
"Mr Rawson said he was aiming for [her] eye, neck and heart."
In October 2017, Rawson's mother had contacted mental health services when he wasn't eating and said he could hear God's voice at times.
A doctor found no evidence of mental illness but the possibility of autism.
No medication was prescribed until a second review in November, but Rawson did not take it.
Rawson's mother said he had an outburst on June 24, 2018, claiming he was a prophet and declaring "doom and gloom" on her and her partner.
Rawson said he was a Christian and acknowledged that his religious views might have been regarded as extreme.
"He has read the Bible cover to cover and believes this makes him a 'special person'. He has conducted Bible studies while incarcerated and invited other inmates to join him. Mr Rawson said he believed he was God's special servant with a special destiny."
According to his father, Rawson said at the time of the offending, "I'm not punishing you, Dad, Jehovah is".
Rawson said he was convinced that God was working through him because his father had committed adultery by having sexual relations with someone other than his mother.
Dr Shailesh Kumar, a specialist forensic psychiatrist, said Rawson had taken edible cannabis that night.
Kumar gave a provisional diagnosis of schizoaffective disorder with abnormal personality traits following childhood trauma.
Dr David Street, a consultant psychiatrist, said Rawson said he tried to kill his stepmother because she "sucked the life out of us and broke my family up".
Street also diagnosed Rawson with schizophrenia and said the offending appeared to have been done in the context of religious delusions.
Dr Annette van Zeist-Jongman, also a psychiatrist, said that when she met Rawson in February 2019 he was "clearly delusional".
Justice Kit Toogood has requested Dr van Zeist-Jongman "determine the most suitable method of dealing with Mr Rawson", whether that meant being a special patient under the Mental Health Act 1992 or as a special care recipient under the Intellectual Disability Act 2003.