Who said "Change is the only constant, even for immortals."?

This quote is attributed to Thor (The Avengers).

Change is the only constant, even for immortals. - Thor (The Avengers)

"Change is the only constant, even for immortals."

Thor (The Avengers) Change

"I am Thor, god of thunder!"

"You lack the strength to wield such power."

"I have nothing but respect for you, and your work."

"There are no men like me."

"Change brings new opportunities."

"Every day is a new opportunity."

"Healing doesn't mean forgetting."

"You either get better or you get bitter."