Ed Sheeran apparently vowed to quit music if he's found guilty of plagiarizing Marvin Gaye's 'Let's Get It On'

• Ed Sheeran testified on Monday in his plagiarism trial in federal court in Manhattan.
• The singer is accused of copying Marvin Gaye's "Let's Get It On" for his 2015 hit "Thinking Out Loud."

Ed Sheeran vowed to be "done" if a jury finds him guilty of plagiarizing Marvin Gaye's 1973 soul classic.

The chart-topping singer testified on Monday in federal court in Manhattan. He's been accused of copying "Let's Get It On" to create his 2015 hit single "Thinking Out Loud."

"If that happens, I'm done, I'm stopping," Sheeran said when asked about the toll the copyright trial is taking on him, according to the Daily Mail. He was apparently referring to his record-breaking music career.

"I find it really insulting to devote my whole life to being a performer and a songwriter and have someone diminish it," he continued.

Sheeran is being sued by relatives of Gaye's songwriting partner, Ed Townsend, including his daughter Kathryn Griffin Townsend, his sister Helen McDonald, and the estate of his late wife, Cherrigale.

Townsend's relatives claim that "Thinking Out Loud" bears "striking similarities" to "Let's Get It On," including a similar chord progression.

Sheeran has denied the allegations and told the court on Monday that "Thinking Out Loud" is a unique composition.

"I know the chords that I'm playing on that guitar," he said in a heated exchange with a plaintiff's lawyer, as reported by Insider's Laura Italiano.

He previously told the court that "pop songs are built on building blocks that have been freely available for hundreds of years," per Rolling Stone.

Townsend's relatives are seeking an unspecified payout and hoping to bar Sheeran from performing "Thinking Out Loud" at live shows.

Gaye's children previously won $5 million after suing Pharrell and Robin Thicke for copyright infringement in 2015.

A jury found the artists guilty of co-opting pieces from Gaye's "Got To Give It Up" for their 2013 hit "Blurred Lines." It's now seen as a landmark case for copyright claims in music, with artists like Questlove warning that it could have a chilling effect on creativity.