Advocates for preserving traditional marriage “will not participate in any form of hate speech”, last night’s gathering on the topic heard.

Instead, visiting American speaker Ryan Anderson outlined a definition of marriage as inherently the domain of procreation and child-rearing.

Dr Anderson told an audience at Heritage Worship Centre that the price of the “genderless” redefinition inherent in accepting same-sex marriage could be summed up as “ideas have consequences — and bad ideas have bad consequences”.

Prompting a murmur of approval from the crowd of about 300, Dr Anderson added: “In fact, to suggest that a child deserves a mother and father might be rendered hate speech.”

Changing marriage could be “more about the desires of adults involved, and less about the rights and needs of children involved”.

Heterosexuals, and not homosexuality, resulted in the switch from a strong marriage culture to “a hook-up culture and non-marital child-bearing”, Dr Anderson said.

Last night’s talk, his first of two, was opened by Henry Dowling of the group Concerned Citizens of Bermuda, a group that has garnered some 7,100 for its online petition that marriage should remain “ordained by God, and between man and woman”.

Dr Dowling said the group has been pleased to secure an auditorium, after the Hamilton Princess, Bermuda cancelled their room rental, citing “anti-diversity discussions”.

Opening his talk, Dr Anderson said he had been pondering “what marriage is, why it matters, and the consequences if your Government was to redefine it”.

“We all want marriage equality,” he said. “What we disagree with is what constitutes a marriage.”

He maintained that traditional marriage upheld three pillars: “monogamy, exclusivity and permanence” and said that absentee fathers and fragmented families were symptoms of a worsening societal trend.

He asked: “How do we teach that fathers are essential, if the law redefines marriage to say that fathers are optional?”

Despite the shared ideals among the group, the prevailing view among many was that regardless of the debate, same-sex marriage was inevitable.

Dr Anderson said: “Now is the time not to say it’s inevitable. Now is the time to engage.”