…expect the best at all times. Never think of the worst. Drop it out of your thought. Let there be no thought in your mind that the worst will happen. Avoid entertaining the concept of the worst, for whatever you take into your mind can grow there. Therefore, take the best into your mind and only that. Nurture it, concentrate on it, emphasise it, visualise it, prayerise it, surround it with faith. Make it your obsession. Expect the best and spiritually creative mind power aided by God power will produce the best.
The Power of Positive Thinking for Young People Norman Vincent Peale p.94