An unbelieved truth can hurt a man much more than a lie. It takes great courage to back truth unacceptable to our times. There's a punishment for it, and it's usually crucifixion.

The remark contrasts the relatively simple harm of deception with the deeper danger of a truth that a community refuses to accept. Steinbeck’s point is social as much as personal: when a culture’s interests, fears, or orthodoxies are threatened, it may punish the truth-teller more severely than the liar, because the truth demands change. The line about “crucifixion” invokes the archetype of the rejected prophet—someone whose moral or factual clarity becomes intolerable to the prevailing order. Read this way, the quote is less about abstract epistemology than about courage, conformity, and the political cost of dissenting speech.