He continued to spend the money the next day and then lost the entire amount after an associate took the money from his pocket while he slept in a sleep out at a Napier address.
Mr Bishop and his friend tried to search for the associate the next day but couldn't find them and eventually gave up.
Later that day he went to his uncle's address to explain what had happened where an argument broke out and Timu punched him in the head; causing him to fall against a metal fence and rip his ear.
Meanwhile Mr Bishop's friend went to a Napier address, still looking for the associate who had taken the money, when Timu arrived with his nephew in the car.
Mr Bishop had told his uncle he thought she may have been involved in taking some of the money; an accusation put to her by Timu.
His friend repeatedly told him she wasn't involved and didn't know where the associate was before Timu told her he would follow her to her house because he wasn't leaving without his money.
Once at her house, she agreed to go with the pair in Timu's vehicle to try find the associate, but returned several hours later after they couldn't locate him.
Timu then told her he would take her vehicle as security until the money was returned.
She told her father what was happening and, after he argued with Timu for some time, her mother eventually called police.
When police arrived Timu explained that his nephew had been "rolled' and he was trying to sort it out.
At sentencing today defence lawyer Eric Forster submitted Timu was remorseful and had not offended since 2003.
"This man does good work in the community. His explanation to the probation officer was that people who have more dysfunctional lifestyles dragged him into something he should have known better to become involved with."
Crown prosecutor Clayton Walker said Timu had punched his nephew "by way of punishment" and that his behaviour toward his friend and her parents had been "aggressive and intimidating"
Judge Geoff Rea described the injury sustained by Mr Bishop as "serious" and needed stiches to repair a 3cm laceration to his ear, but added he had kept out of the courts for almost a decade and a half.
He noted Timu had endeavoured to make a better life for himself and his family, but said there was "no doubt" he had used his gang status as an intimidation factor in the incident.
"I just hope the irony of all of this isn't lost on you. You claim to be a crusador to help people getting involved with methamphetamine. Yet on the other hand you are prepared to fund, in the thousands of dollars, the purchase of cannabis."
In the past Timu has been vocal about his commitment to White Ribbon's anti-violence message and acts as a regional field worker for the nationwide change trust, Waka Moemoea that helps families and youths communities such as Flaxmere and Camberley.
Sociologist and gang expert Jarrod Gilbert said the defendant's conviction did not negate his prosocial community work and messages.
"The great difficulty people like Rex have got is that positive change is never easy and rarely is it absolute, at least initially. Changing their behaviour is dissident; it happens over time."
"The endeavour to turn gangs around and turn a new leaf with certain individuals and in certain chapters of gangs is genuine. But to expect that to happen as a smooth and clean process without the odd hiccup along the way is just unrealistic."
Violence in gang culture was "without a doubt" decreasing, he said, but this was as much a family matter as it was a gang one.
"It's come about because of a dispute in the family, not in a gang. As a leader of course people look to him to set an example but in a realm and world of gangs, the violence that's been displayed here is at a very mild end of the spectrum.
"People may be shocked by it but we've got to understand we're dealing with a completely different set of values at play."
Judge Geoff Rea passed a sentence of seven months' home detention, which he will serve at his Flaxmere address.
