I WILL PERSIST UNTIL I SUCCEED, Og Mandino

I will persist until I succeed.
I was not delivered unto this world in defeat, nor does failure course in my veins. I am not a sheep waiting to be prodded by my shepherd. I am a lion and I refuse to talk, to walk, to sleep with the sheep. I will hear not those who weep and complain, for their disease is contagious. Let them join the sheep. The slaughterhouse of failure is not my destiny.
I will persist until I succeed.
The prizes of life are at the end of each journey, not near the beginning; and it is not given to me to know how many steps are necessary in order to reach my goal. Failure I may still encounter at the thousandth step, yet success hides behind the next bend in the road. Never will I know how close it lies unless I turn the corner.
Always will I take another step. If that is of no avail I will take another, and yet another. In truth, one step at a time is not too difficult.
I will persist until I succeed.
Henceforth, I will consider each day's effort as but one blow of my blade against a mighty oak. The first blow may cause not a tremor in the wood, nor the second, nor the third. Each blow, of itself, may be trifling, and seem of no consequence. Yet from childish swipes the oak will eventually tumble. So it will be with my efforts of today.
I will be liken to the rain drop which washes away the mountain; the ant who devours a tiger; the star which brightens the earth; the slave who builds a pyramid. I will build my castle one brick at a time for I know that small attempts, repeated, will complete any undertaking.
I will persist until I succeed.
I will never consider defeat and I will remove from my vocabulary such words and phrases as quit, cannot, unable, impossible, out of the question, improbable, failure, unworkable, hopeless, and retreat; for they are words of fools. I will avoid despair but if this disease of the mind should infect me then I will work on in despair. I will toil and I will endure. I will ignore the obstacles at my feet and keep mine eyes on the goals above my head, for I know that where dry desert ends, green grass grows.
I will persist until I succeed.

The Greatest Salesman in the World
Og Mandino