Never give.... in....
I always thought it was "Never give up!" but... it's actually...
"This is the lesson: never give in, never give in, never, never, never, never - in nothing, great or small, large or petty - never give in except to convictions of honor and good sense. Never yield to force; never yield to the apparently overwhelming might of the enemy."
~ Winston Churchill
and I think this might be the rest of the quote? I am unsure if it is but: "Whatever you do, never give in - and never, never, never give up."