Wisdom: Do not preach wisdom to a man whose heart is hard

Do not preach wisdom to a man whose heart is so obstinately
hard that it will not soften or melt in feeling for others. He will be
unable to understand your true worth and the maturity of your
wisdom. Your wisdom will not penetrate him; he will convert
it into a hard rock and hurl it back to you. Not only that, he will
pick up the black rocks from the mountain of his heart and throw
them at you, too. As a result, you may have to face many tribula-
tions. If you want to achieve mastery over your life, you must
learn to avoid such people and go on your way.

Muhaiyaddeen, M.R. Bawa. The Golden Words of a Sufi Sheikh. Philadelphia:Fellowship Press, 1981, 2006