"The Festival of Dangerous Ideas is intended to be a provocation to thought and discussion,rather than simply a provocation,"the Opera House wrote on Facebook.
"It is always a matter of balance and judgement,and in this case a line has been crossed."
"It is clear from the public reaction that the title has given the wrong impression of what Mr Badar intended to discuss. Neither Mr Badar,the St James Ethics Centre,nor Sydney Opera House in any way advocates honour killings or condones any form of violence against women."
Mr Badar told Fairfax Media on Tuesday that the session's cancellation is revealing of the extent and influence of Islamophobia in Australia.
He blamed"baseless hysteria"for gagging the expression of ideas.
"It also highlights,once more,that freedom of speech is a tool of power and nothing more,"he said.
By Tuesday night the link to Mr Badar's talk on the Festival's website had been taken down.