The funnyman made the 300 guests at the event in Mexico laugh, but also set aside a few poignant words for his friend as he tied the knot with the Victoria's Secret model.
A source told E! news: ''Jonah was hysterical. He was telling so many jokes, but then in the middle would be so sweet and sincere.
''He also talked about how sweet Behati is and how perfect they are for one another.''
One of Jonah's quips was about how he and Adam used to skateboard with Robert Downey Jr. and Stevie Nicks when they were young.
The source explained: ''He set up the joke perfectly. His timing was amazing. Everyone was giggling.''
As well as Jonah officiating, Prinsloo's dad, who is a minister, also gave the happy couple a blessing as they married on the beach in the evening.
During the service the bride and groom read vows that they had written themselves, and afterward guests were treated to a reception with plenty of food and drink.
The source added: ''It was all fresh, seared tuna, lovely salads, everything was organic and amazing. Drinks were flowing. There was every kind of mojito you can imagine.''
Adam and Behati are now set to honeymoon in South Africa.
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