When Michael Daley saw a blind man in a help centre he accused him of being a fraud and picked a fight with him, a court heard.
Daley was sitting opposite Shaun O'Fahy at Bristol Methodist Centre when he muttered: "People who are supposed to be blind are riding bikes and defrauding the DHSS".
Mr O'Fahy - who is registered blind due to restricted vision but can ride a cycle and use a computer - then accompanied him to a park opposite where they had a fight and Daley produced a knife.
Daley, 55, of Kiln Court in Easton, pleaded guilty to threatening with a blade and racially aggravated harassment in July last year.
He also admitted possessing a blade and a racially aggravated public order offence on March 12 this year.
Judge Michael Longman handed him a 20 months jail term, suspended for two years.
Catherine Flint, prosecuting via video link due to coronavirus lockdown, told Bristol Crown Court Daley made the jibe about Mr O'Fahy before they went to a nearby park and exhanged blows.
The court heard Daley waved a knife and was heard to say: "I'm going to stab you" before someone intervened and Daley ran off.
Three weeks later Mr O'Fahy was at Junction 3 Library in Easton when he had a second exchange with Daley, who racially abused him, Miss Flint said.
Daley also admitted having a knife when he racially abused Lisa Curas at Waylands Court in Fishponds, after she asked him to buy her £15 worth of tobacco.
Catherine Spedding, defending via video link, said her client suffered from anxiety and depression.
She told the court that after drinking and drug-taking, as well as being homeless, her client had since secured accommodation and had started treatment for mental health issues until that was disrupted by the pandemic.
Miss Spedding said: "He does not want to keep coming back before the court.
"He is 55, he wants to live a quiet life."
