Peacefulness is an inner sense of calm - it comes from becoming still - in order to reflect and meditate on our inner wisdom and receive answers. A peaceful heart is one that is free from worry and rouble. It's becoming quiet so we can look at things quietly so we can more clearly understand them and thus come up with creative solutions. It is learning to live in the present. Freedom from desire leads to inner peace.
What makes a kingdom great is its being like a down-flowing river,--the central point towards which all the smaller streams under Heaven converge; or like the female throughout the world, who by quiescence always overcomes the male. And quiescence is a form of humility.
The men who are great live with that which is substantial, they do not stay with that which is superficial; they abide with realities, they do not remain with what is showy. The one they discard, the other they hold.