I hugely admire Swami Vivekananda. His quotes are simply exceptional.
To give you a sample.
This is what he says about perseverance :
To succeed, you must have tremendous perseverance, tremendous will. "I will drink the ocean," says the persevering soul, "at my will mountains will crumble up." Have that sort of energy, that sort of will, work hard, and you will reach the goal.