As it turns out, weddings in the days of yore sometimes followed kidnappings. This explains not only the role of the best man but also why the bride and groom customarily leave the wedding celebration before everyone else. It’s symbolic of the groom stealing away with his bride, taking her from her family and into a new life with him.
In medievel Europe, carrying a bride into her new home prevented her from seeming too enthusiastic about losing her virginity. By picking her up and taking her into their home, the groom provided an alibi for his wife’s chasity.
The threshold of the home was thought to be rife with unattached spirits. A bride was considered particularly vulnerable to spirits especially through the soles of her feet. By carrying her the groom was covering all his bases.
Much, if not all, of the original meaning behind a groom carrying his bride across the threshold has been lost in modern weddings. The practice is more done with humour or as a photo op as today’s couples are not entirely sure why to do it. But, it’s better safe than sorry right?