“You have to be a strong man, and your life has to be truthful.”

“What is a truthful life?”

“A life lived with deliberateness, a good, strong life.”

A conversation between don Juan Matus and Carlos Castaneda, from The Teachings of Don Juan: A Yaqui Way of Knowledge

The context of the above quote is a conversation between don Juan and Carlos about how one can attract Mescalito as an ally and get him to accept the individual completely. I think the wisdom can be applied more generally, too.