"prove commitment" is correct and usable in written English.
You can use it when you want to express the need to demonstrate or show dedication or loyalty to something. For example: "I need to prove my commitment to this project by continuing to work hard and put in extra effort."
"Steinhoff is a well-capitalised, international business with a clear and proven commitment to value retailing," he said.
Banking licenses could be made more readily available to well-capitalized entities with strong management teams and a proven commitment to serving local business.
The new approach to attracting recruits will be based on the individual's proven commitment to carry out the tasks set.
But what is needed is a functioning five-member commission, including a strong leader with a proven commitment to investor protection and deep experience in markets, regulation and securities law enforcement.
The theatre has won support from several figures in the arts, including Sir Nicholas Hytner, director of London's National Theatre, who said Rubasingham and her board had a proven commitment to Jewish culture.
Anne Longfield, the children's commissioner for England, publicly backed the appointment in a letter to Morgan: "Amanda has an impressive breadth of experience across the education sector and proven commitment to raising standards for children and young people".
Schiller was a student of realpolitik, and one of the play's great scenes shows the duplicitous Leicester trying to talk his way out of his proven commitment to Mary.
"Georgia, and the nation as a whole, deserves a judge with a proven commitment to equal justice and constitutional rights".
Students generally are accepted as trainee teachers if they possess the virtues of intellect, good character, a proven commitment to social development and love for children.
"Jeb has a consistent, proven commitment to promoting legislation that would advance the pro-life cause and appointing reliably conservative justices". .
