Who said "The impossible is where the real adventure begins."?

This quote is attributed to The Flash (DCEU).

The impossible is where the real adventure begins. - The Flash (DCEU)

"The impossible is where the real adventure begins."

The Flash (DCEU) Adventure

"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."

"The greatest adventure is life itself."

"The adventure of life begins with a single step."

"Adventure finds you when you stop running."

"Fortune and glory, kid."