James Harold, 31, of Henry Street, Warrnambool, pleaded guilty in the Koori division of Warrnambool Magistrates Court to recklessly causing serious injury and bail offences.

The court heard on December 30 last year, a 61-year-old male rang 000 about 6pm to report he had been stabbed in the upper leg with a knife at his home in Warrnambool's Wellington Street.

Police and ambulance attended the scene. The victim was located lying on the front porch with a towel wrapped around his leg.

He told police he was making a cup of coffee when Harold, who was known to him, stabbed him in the leg with a knife.

The victim was conveyed to Warrnambool Base Hospital in a life threatening condition.

He drifted in and out of consciousness and underwent numerous blood transfusions.

When the victim regained consciousness, he told police he was stabbed without warning or provocation.

Harold was arrested at his Henry Street property later that evening.

At the time of the offending he was on bail for breaching a court order just six days earlier. He became enraged on Christmas Day, throwing a kitchen drawer across the kitchen of his home and causing his grandmother to be scared and call for help.

When police arrived, Harold was located on the roof. He was agitated and abusive to police.

After about two hours of negotiations, he came down and was subsequently arrested.

Indigenous elder Uncle Lenny Clarke said the offending was "very bad".

"I find it absolutely scary and weird," he said.

"To sit in someone's home and just get up and attack them for no reason at all.

"But you do say you were on the dreaded ice."

The court heard Harold had been a consistent ice user since he was 15.

Harold said the drugs "make you think people are talking about you."

He told the court he had known the victim for 20 years.

"He was my mate. I feel bad inside for him," he said.

Harold was ordered to undergo assessments for a justice plan and community corrections order, as well as a Forensicare psychiatric report.

He will be sentenced on December 13.

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