The Northern Ireland Health Minister Robin Swann has written a scathing opinion piece for Rolling Stone magazine about Sir Van Morrison.
Last week the singer announced three new songs that protest against the coronavirus lockdown.
In the lyrics, he claims scientists are "making up crooked facts" to justify measures that "enslave" the population.
Mr Swann said the songs were "dangerous", challenging Sir Van to present his own scientific facts.
The minister has echoed those thoughts and expanded upon them in a highly critical 'op-ed' piece for Rolling Stone magazine.
The American monthly title focuses on popular culture, including music, entertainment and politics.
Describing the piece, Rolling Stone's editors said: "Swann vacillates between disappointment, bemusement and anger at the new cause of one of Northern Ireland's most celebrated singers."
In the article Mr Swann criticised Sir Van and the potential damage he could do to public health messaging around Covid-19 in Northern Ireland.
He wrote: "We in Northern Ireland are very proud of the fact that one of the greatest music legends of the past 50 years comes from our part of the world.
"So there's a real feeling of disappointment - we expected better from him.
"If you see it all as a big conspiracy, then you are less likely to follow the vital public health advice that keeps you and others safe."
He added that governments across the world are "struggling" to find their way through the pandemic and its "right and proper" to debate and question policies.
"But Van Morrison is going way beyond raising questions", he said.
"He is singing about 'fascist bullies' and claiming governments are deceiving people and wanting to 'enslave'."
Mr Swann said the songs are a "smear" on those involved in the public health response to the virus.
"His words will give great comfort to the conspiracy theorists - the tin foil hat brigade who crusade against masks and vaccines and think this is all a huge global plot to remove freedoms."
He added: "It's all bizarre and irresponsible.
"I only hope no one takes him seriously. He's no guru, no teacher."