CATECHISM OF THE CATHOLIC CHURCH
SECOND EDITION

Paragraphs 2467–2471

2467 Man tends by nature toward the truth. He is obliged to honor and bear witness to it: "It is in accordance with their dignity that all men, because they are persons . . . are both impelled by their nature and bound by a moral obligation to seek the truth, especially religious truth. They are also bound to adhere to the truth once they come to know it and direct their whole lives in accordance with the demands of truth."
2468 Truth as uprightness in human action and speech is called truthfulness, sincerity, or candor. Truth or truthfulness is the virtue which consists in showing oneself true in deeds and truthful in words, and in guarding against duplicity, dissimulation, and hypocrisy.
2469 "Men could not live with one another if there were not mutual confidence that they were being truthful to one another." The virtue of truth gives another his just due. Truthfulness keeps to the just mean between what ought to be expressed and what ought to be kept secret: it entails honesty and discretion. In justice, "as a matter of honor, one man owes it to another to manifest the truth."
2470 The disciple of Christ consents to "live in the truth," that is, in the simplicity of a life in conformity with the Lord's example, abiding in his truth. "If we say we have fellowship with him while we walk in darkness, we lie and do not live according to the truth."
2471 Before Pilate, Christ proclaims that he "has come into the world, to bear witness to the truth." The Christian is not to "be ashamed then of testifying to our Lord." In situations that require witness to the faith, the Christian must profess it without equivocation, after the example of St. Paul before his judges. We must keep "a clear conscience toward God and toward men."