To mark the special occasion, the comedian, 56, posted a heartwarming photo of the couple beaming for the camera. In the snapshot, Melanie is pictured wearing her '90s wedding dress complete with giant, puffy sleeves, delicate gold beading and satin corsages.
She wore her natural grey locks down loose and finished off her outfit with a pair of round sunglasses. John, meanwhile, opted to wear a smart ensemble featuring dark blue jeans, a smart powder blue shirt and a navy jumper.
In the caption, John penned a wholesome message highlighting the inevitable ups and downs of their 30-year marriage. "30 years ago today @melbish1 walked down the aisle in that dress," he shared.
"She took my breath away then and still does today. Last weekend we spent time with our bridesmaids (Jane and Jane) ushers (John, Paul, Sergie and Jimmy) and best man (our Eddie) who are still the most important people in our lives and whose support has helped reach this far."
Reflecting on some of their challenges as a couple, he continued: "It is amazing how quickly three decades pass. In that time there have been a million laughs and a million tears. Life doesn't always comply with the perfect world that social media presents - no matter who you are there are days when it's hard to see a way through.
"There are some things I wish I had done better and there are others that blow my mind because they went so well. After 30 years of marriage the one lesson I have learnt is that I am a stronger, better man because she is the person who holds my hand and guides me through when all I can see is darkness. She still fits in the dress and my heart still fits in her pocket."
The comedian's followers inundated the comments section with sweet messages. "What a beautiful tribute to your wonderful Mel. 30 years later, how lucky you both are to still have so much love and respect for each other," while a second noted: "Beautiful. You have such a way with words."
A third remarked: "So lovely, congratulations to you both," and a fourth added: "No mean feat, congratulations to you both, lovely words."
Whilst the couple have clearly been going from strength to strength, John and Melanie hit a rough patch in 2000 resulting in a brief split. After more than a year and a half apart, the couple inadvertently reunited at one of John's comedy shows in Manchester.
They reconciled shortly after their unexpected reunion and haven't been apart since. Together they share three sons: Joe, 28, Luke, 26, and youngest, Daniel, 24.
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