Catechism of the Catholic Church §2469 — excerpt
"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.
This translation is under copyright, so only the cited words are quoted here. Follow the link for the full text. Translation: English translation of the Catechism of the Catholic Church, 2nd ed. (Libreria Editrice Vaticana), as posted at vatican.va.
Also cites: St. Thomas Aquinas, STh II-II 109, 3 ad 1 · St. Thomas Aquinas, STh II-II, 109, 3, corp. art