This was all written 500 years ago, in a different time and place, with a different language and culture. So do not mistake the meaning of “criminal.”
This is crucial. Here he is telling you to seek a variety of adversities.
Think deeply on this, for it is what divides men into those of character, and those of shallowness. You must purposely seek out difficulty and challenge, or forever have a reservoir of fear and doubt deep within you.
Some face fearsome beasts, others climb wild mountains. For some they must face opponents and know the clash of arms.
And you will know such me by their posture and the look in their eyes. Adversity is the heat needed to hatch the egg of courage.
“When Heaven is about to confer an important office upon a man, first it embitters his heart in its purpose,; it inflicts upon him want and poverty and confounds his undertakings. In this way it stimulates his will, steels his nature, and thus makes capable of accomplishing what he would otherwise be incapable of accomplishing.”
What Musashi is saying is, don’t wait for Heaven to challenge you, seek the challenges yourself.
I know that most of you feel drawn toward activities that would develop your spirit. I, and most of my friends have; had motorcycles, jumped from planes, made long and dangerous voyages, and practiced martial arts, with a leaning toward full-contact. And so we know ourselves, and others.
Writing this book is not easy for me, but having at least some discipline I can make it happen.
A work of caution here. This is not a suggestion to engage in stupidity. Breaking the laws of man or nature will not enhance you, but instead the human race, in a Darwinian sense. You take calculated risks. But you prepare for failure, such is the strategy of a martial artist.