"It's unnatural," Cameron said on the show Friday. "I think that it's - it's detrimental, and ultimately destructive to so many of the foundations of civilization."
Piers Morgan openly disagreed with Cameron, claiming that if one of his sons came out, he would say, "'that's great son, as long as you're happy.'"
Since becoming a born-again Christian at the age of 17, Cameron has become well-known for his work spreading his Christian evangelist beliefs. On Saturday, the Gay & Lesbian Alliance Against Defamation fired back at Cameron.
"In this interview, Kirk Cameron sounds even more dated than his 1980s TV character," GLAAD's senior director of programs, Herndon Graddick said in a statement. "Cameron is out of step with a growing majority of Americans, particularly people of faith who believe that their gay and lesbian brothers and sisters should be loved and accepted based on their character and not condemned because of their sexual orientation."
Cameron, 41, went on to blast marriage equality in the same interview. "Marriage is almost as old as dirt, and it was defined in the garden between Adam and Eve," he said. "One man, one woman for life, till death do you part. So I would never attempt to try to redefine marriage. And I don't think anyone else should either. So do I support the idea of gay marriage? No, I don't."
To that, Graddick responded: "With an increasing number of states recognizing marriage equality, Americans are seeing that marriage is about committed couples who want to make a lifelong promise to take care of and be responsible for each other and that gay and lesbian couples need equal security and legal protection. That's not 'redefining' anything."
What do you think of Cameron's comments?