How true this is. If you do not believe in yourself, who will? Believing in yourself has a power unto itself. It gives you strength.
The power of your convictions gives you the fortitude to persevere when others tell you it cannot be done. If not for perseverance, we would still be living in caves. Every invention that has brought us to this place in time was developed by a person manifesting the power of God within. As it says in the Bible, there is nothing new under the sun. (Ecclesiastes 1:9)
The trick in manifesting your inner power is to be aware and attuned enough to your Self to pull it out. If you have an idea, something that you have pulled out of the stream of universal consciousness then act on it immediately. If you do not, someone else will because now you have brought that particular thought into the mainstream of human thought and anyone can grab it and run with it.
Do not hesitate and do not let your doubts and fears impede you. Be determined in your pursuit if you believe that you are right and that your thought is worthy of being manifested.