Definition & Meaning of "[put] {one's} money where {one's} [mouth] [is]"

What is the origin of the idiom "put one's money where one's mouth is" and when to use it?

The idiom "put one's money where one's mouth is" originated from the idea that actions speak louder than words, particularly when it comes to backing up one's statements or claims with financial commitment or tangible action. The phrase signifies the act of demonstrating genuine belief or commitment by investing one's resources or taking practical steps to support or fulfill what one has advocated or promised. The phrase is commonly used to challenge someone to back up their assertions or promises with concrete action or financial support.