"He disguised himself."
His victim felt "terror" as Bowden attacked him from behind, Mr Blaschke said.
"[The victim] will continue to suffer psychologically from ongoing effects ... it was virtuitous violence," he said.
The crown asked the court for a sentence of seven years.
Defence lawyer Simon Hewson said the offending was out of character for his client who had no previous convictions.
Bowden was prepared to undergo Restorative Justice with the victim when the victim was ready, he said.
"His cell door is always open to the victim ... he wishes to partake in Restorative Justice."
He couldn't remember the events of the robbery but put his hand up when questioned by police, Mr Hewson said.
Bowden was taking advantage of alcohol and drug addiction counselling while on remand, the lawyer stated.
"He is motivated to do this."
Mr Hewson asked the judge to consider Bowden's age and the lack of previous offending for sentencing to give him "hope".
"There is no doubt there is remorse ... he sees this as a turning point for him ... he can grow from this."
In sentencing, Judge Large said the attack was vicious with Bowden stabbing Mr Frost four times with such force the knife handle broke.
"He suffered terror from the event that night. He is still suffering long term effects from what you did that night."
The judge noted Bowden had twice tried to enter the station but stopped when customers arrived, waiting until the victim was alone.With a starting point of seven years, the judge gave Bowden a discount of two years, sentencing him to five years imprisonment.
Outside court Mr Frost said he was relieved it was finally over for him and Bowden.
"I'm glad he had the fortitude to take it on the chin and say he did it," he said.
He wakes at night, reliving the trauma.
"I can now begin to heal."
Mr Frost would like to thank the community for their support since the robbery.
"Everyone has been so supportive. We are so grateful."