Your mind will be like its habitual thoughts; for the soul becomes dyed with the color of its thoughts. - Marcus Aurelius
How often do we tell ourselves "it's okay to think about it, I just shouldn't do it"? The fact is, it is not okay, not because "god is watching" or something like that, but because what we think about will eventually manifest itself in our behavior.
Likewise, however, good thoughts also manifest themselves in our lives after thinking about them often enough. Visualize your goals 5 years from now daily, and be very vivid and specific, and it's likely to become true.
Skeptical? So was I 5 years ago, but it all worked out 100%.
For more short meditations like this, go to bit.ly/morningfeeling