Adil Bhatti, who fronts Glasgow's Pollokshields Development Agency (PDA), said on social media that he was going for an eye check-up as he did not "want to be called ranjeet Singh lol". Singh was the founder of the Sikh empire and is a holy figure in the religion.
A Sikh leader last night condemned the comments.
The PDA was incorporated in 2006 for the benefit of people in Pollokshields, but this was expanded recently to included the population of Glasgow South. Its founding charter states that it should promote the area's inhabitants without regard for sex, sexual orientation or religious and political opinions. Promoting racial equality is also listed as an aim and objective. However, Bhatti's remarks are said to have damaged inter-faith relations.
Bhatti, who is also listed as a director of the Ethnic Minorities Law Centre, is a well-known political activist in the city. He was a Labour supporter but quit the party in 1990s and defected to the SNP, where he became convener of Scottish Asians for Independence.
However, he left the SNP in a blaze of publicity in 2012, citing the Nationalists' decision to reverse its anti-Nato stance. He has since rejoined Labour.
Speaking to the Sunday Herald, Bhatti last night, he said he had used the reference to Ranjeet Singh "as a joke". "I didn't mean to harm anyone's feelings. If someone feels that way, I would apologise to them."
Charandeep Singh, the general secretary of the Glasgow Gurdwara, a place of worship for Sikhs, said: "If Adil Bhatti is found to have ridiculed this important historical figure and regards his visual disability something to mock then I am seriously concerned about his judgment.
"Mr Bhatti, who occupies senior positions on public bodies, has insulted both the Punjabi Sikh community and those who are visually impaired. He must answer how he can credibly maintain a public role in an organisation representing Pollokshields."
Norman MacLeod, an SNP councillor in Pollokshields, said: "Adil Bhatti and his Labour friends might find visual impairment funny, and that's simply not acceptable."