What exactly does this phrase mean? Specifically, is groins used here as an idiom? Or just coined by the speaker here? Here is the context:
What I hope for the future is that all that major religions of the world (the chief promulgators of homophobia, after all) will finally lose their grip on the groins of their followers and begin preaching decency and human kindness. Fat chance, I know, but a boy can dream.
The article in which I saw this phrase was Armistead Maupin: ‘When Stonewall Happened, I Was Smoking My First Dick, So I Was a Little Distracted’
I know the meaning of grip. It’s the groins that I don’t understand. Why should the speaker choose groins instead of maybe arms or heads or minds? I mean, is gripping someone’s groins an idiom used by many people, or is it just a choice made by the speaker?
Is it a metaphor of one’s sexuality, taking into consideration homophobia in the context of the entire article?