A Florida pastor is claiming a Guinness World Record for the longest speech ever following a marathon sermon.

Pastor Zack Zehnder from The Cross church in Mount Dora preached for 53 hours and 18 minutes, smashing the previous record which was a mere 48 hours and 31 minutes.

Zehnder, whose father, grandfather, and great-grandfather were all ministers in the Lutheran Church, undertook the challenge to raise funds for an addiction recovery ministry run by the Hand in Hand charity. The Powerhouse Addiction Recovery Program will help people with addictions including alcohol, drug and sex among others. The target of $100,000 was surpassed on Monday with a $10,000 cheque that took the total to more than $102,000.

Hand in Hand executive director Dave Douglas said: "I'm blown away by the generosity of so many people who have given their time and talents to support this cause."

Zehnder's sermon began at 7am on Friday, November 7 and continued until 7.32 am on Sunday, November 9. He was only allowed a five-minute break every hour.

He broke his address into 50 different parts and preached through the Bible from Genesis to Revelation, using notes and a pre-prepared PowerPoint presentation. A back-up team of nurses ensured that he was fit to continue and was receiving proper nutrition, though he was forced to preach with his mouth full as he was only allowed to stop speaking for 30 seconds at a time.

At the end of his sermon, clearly exhaused, he said: "The one thing I've seen is God's ridiculous pursuit of you and me. Even when we fail, even when we sin, and we all have, he never gives up on us." He concluded with a quote from the last sermon preached by his grandfather.

The previous holder of the title for the longest speech was Vickrant Mahajan in Kashmir, India.

Zehnder's claim has been received by Guinness World Records, but it will take up to eight weeks for it to be verified.