This world “powerful” is to be applied to your personal life. When you, in your life, achieve something, you will feel powerful as if you are the most able person in the world. If it is the case, you must be careful or unfortunate may fall upon you.
On the other hand, you must think that you are a powerful person. But such feeling is not to represent that you are the one of proudness. Instead you are a very prudent person to run your life carefully to represent your powerfulness. For example if you pay much attention to your health, controlling your daily life in every good way, such as not over eating, sleep enough and so on, you shall then never be sick, no need to see doctor and eat medicine. It is your greatness.
Therefore, we should apply our carefulness in small matter at our daily life. As long as we handle small matters well, we are a powerful man, or, on the contrary, we may have trouble or disaster.
Sometime few very huge companies suddenly bankrupted for no particular reason. It is because they are not careful to trade their business even their are a powerful company.
In our life, we must think we are powerful, but, on the other hand, we must be humble to deal with everything which we are facing in our everyday life.