CATECHISM OF THE CATHOLIC CHURCH
SECOND EDITION

Paragraphs 2507–2511

2507 Respect for the reputation and honor of persons forbids all detraction and calumny in word or attitude.
2508 Lying consists in saying what is false with the intention of deceiving one's neighbor.
2509 An offense committed against the truth requires reparation.
2510 The golden rule helps one discern, in concrete situations, whether or not it would be appropriate to reveal the truth to someone who asks for it.
2511 "The sacramental seal is inviolable" (CIC, can. 983 # 1). Professional secrets must be kept. Confidences prejudicial to another are not to be divulged.