When barmitzvahs find internet fame, it is often because of their entertainment qualities — think showdancers and catchy pop songs.

Last month, however, Duncan Alpine Sennett caught attention for the power of his reasoning when he gave an impassioned defence of gay marriage in his barmitzvah speech.

Giving the D’var Torah at the Reform synagogue Congregation Beth Israel in Portland, Oregon, Duncan started by discussing traditional marriage as it was transacted in his parsha, “like a business deal” between Jacob and Laban — the father of Rachel and Leah.

Citing the Torah portion Vayetze, he convincingly argued that marriage in the US had moved on from treating women as chattel. Then, having said that it would be “irresponsible to exclude the topic of gay marriage”, he noted that his own parsha undermines the biblical argument that marriage is between one man and one woman.

“My torah portion taught me that the definition of traditional marriage has changed a lot since the days of Torah,” Duncan closes. “So why can’t it change just a little bit more so everybody can marry who they love?”