From My Favorite Gosho, the writings of Nichiren Daishonin:
On Attaining Buddhahood:
"If you wish to free yourself from the sufferings of birth and death you have endured through eternity and attain supreme enlightenment in this lifetime, you must awaken to the mystic truth which has always been within your life. This truth is Myoho Renge Kyo. Chanting Myoho Renge Kyo will therefore enable you to grasp the mystic truth within you. Myoho Renge Kyo is the king of sutras, flawless in both letter and principle. Its words are the reality of life and the reality of life is the mystic law (myoho). It is called the mystic law because it explains the mutually inclusive relationship of life and ALL phenomenon.
Life at each moment encompasses both body and spirit and both self and environment of all sentient beings in every condition of life, as well as insentient beings~ plants, sky and earth, on down to the most minute particles of dust. Life at each moment permeates the universe and is revealed in all phenomena. One awakened to this truth himself embodies this relationship. However, even though you chant and believe in Myoho Renge Kyo, if you think the law is outside yourself, you are embracing not the Mystic Law but some inferior teaching...
when you chant the mystic law and recite the Lotus Sutra you must summon up deep conviction that Myoho Renge Kyo is your life itself."
In other words...you ARE the mystic law...your very life essense is the same as the power of the entire universe.
Nam Myoho Renge Kyo means: I fuse my life with the mystic law of cause and effect through sound vibration.
When you chant these words and think about what you want you get it...and furthermore...you keep getting to a deeper and deeper realization of what you really want in life...as as you do this, if you are chanting, your CONVICTION that you are this law, and that you DESERVE to be happy will grow and grow and grow. And that's also where the real power lives. Because once you experience this you will feel the need within you to tell other people about it...and your benefits will continue to flow and flow and flow!