What has the most power over you? Other people? Your past? Your feelings? The answer is — what you focus on the most in your thoughts — has the most power. An example would be eating. Let's say you want to lose weight. You start your diet thinking about nothing but food. You're thinking about what to eat, when to eat, how much to eat, and where to eat.
As those thoughts become dominate, you start thinking, "I want to stop thinking about food". So, you block them from your mind. In other words, now you're suppressing your food thoughts.
Extremes don't work.
Your power comes when you have balanced thinking about food. You eat when you're hungry. You stop eating when you're full. You can go to the movies and not be moved to buy popcorn just because it smells so buttery.
Mastering your thoughts proves to be the ultimate power.