Who said "I have to keep moving, keep fighting, keep believing."?

This quote is attributed to The Flash (DCEU).

I have to keep moving, keep fighting, keep believing. - The Flash (DCEU)

"I have to keep moving, keep fighting, keep believing."

The Flash (DCEU) Perseverance

"I'm fast. Really fast."

"Time moves differently when you're moving at super speed."

"You gotta embrace what makes you different."

"Running away isn't always the answer, even when you're fast enough to do it."

"Perseverance is the key to success."

"Don't give up on what you believe in."

"I've been through worse."

"You learn to live with the pain."