In a Facebook post, Gabriel explained that he wrote the song a few years ago and it was, in part, "inspired by Muhammad Ali’s life and struggles."
"At the time of his death, when so many people are celebrating his life and thinking about all he achieved, it seemed the right time to release it," he wrote.
5 Songs Inspired by Muhammad Ali
Ali passed away June 3 due to "septic shock due to unspecified natural causes," according to his family.
"I'm Amazing" is Gabriel's first release in nearly three years, following the track "Why Don't You Show Yourself" that was featured in the live concert album and film Back to Front: Live in London in 2013.
Listen to it here: