When Nicole Richie and Joel Madden exchanged vows in Beverly Hills on Saturday, they had a very special man of the cloth helping them out: Rev. Run!

"Joel and Nicole have looked up to Rev. Run, so they wanted him to officiate," a guest of the wedding tells UsMagazine.com exclusively. The Run-DMC rapper and reality star, 46 (real name: Joseph Simmons) is also a practicing minister.

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Explains the guest: "They both appreciate his family values and he is an inspiration for both. They both also respect his faith, too."

The spiritual hip-hop pioneer wasn't the only celeb on hand for the evening nuptials, held at the sprawling home of Richie's singer dad Lionel: Khloe Kardashian and Samantha Ronson were among the approximately 150 guests at the winter-themed affair.

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Also fete-ing the couple? An elephant, which was spotted entering a white tent with other guests before the ceremony got underway.

Together for four years, Richie, 29, and Madden, 31, have two kids: two-year-old daughter Harlow (a flower girl!) and son Sparrow, 15 months.

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"We're really focused on our family, and...we already feel kind of married, you know?" Madden told Larry King in 2009.