Several years ago Rebecca (not her real name) was accused of several misdeeds by a seemingly rational individual who alleged she had violated his workspace.
So I always take pains to have a clear conscience toward both God and man. Acts 24:16
If you try my heart, if you visit me by night, if you test me, you will find no wickedness in me; my mouth does not transgress. Psalm 17:3
The integrity of the upright guides them, but the crookedness of the treacherous destroys them. Proverbs 11:3
Lying lips are an abomination to the Lord, but those who act faithfully are his delight. Proverbs 12:22
Keep your conscience clear, so that, when you are slandered, those who revile your good behavior in Christ may be put to shame. 1 Peter 3:16
Blessed are you when people revile you and persecute you and utter all kinds of evil against you falsely on my account. Rejoice and be glad, for your reward is great in heaven, for in the same way they persecuted the prophets who were before you. St. Matthew 5:11-12.
Watch at all times, praying that you may have strength to escape all these things that will take place, and to stand before the Son of man. St. Luke 21:36.
c.1400, "innocence, blamelessness; chastity, purity," from Old French integrité or directly from Latin integritatem (nominative integritas) "soundness, wholeness, blamelessness," from integer "whole". Sense of "wholeness, perfect condition" is mid-15c.
The Catechism of the Catholic Church
2477 Respect for the reputation of persons forbids every attitude and word likely to cause them unjust injury. He becomes guilty:- of rash judgment who, even tacitly, assumes as true, without sufficient foundation, the moral fault of a neighbor;
- of detraction who, without objectively valid reason, discloses another's faults and failings to persons who did not know them;
- of calumny who, by remarks contrary to the truth, harms the reputation of others and gives occasion for false judgments concerning them.2478 To avoid rash judgment, everyone should be careful to interpret insofar as possible his neighbor's thoughts, words, and deeds in a favorable way:
Every good Christian ought to be more ready to give a favorable interpretation to another's statement than to condemn it. But if he cannot do so, let him ask how the other understands it. And if the latter understands it badly, let the former correct him with love. If that does not suffice, let the Christian try all suitable ways to bring the other to a correct interpretation so that he may be saved.
2479 Detraction and calumny destroy the reputation and honor of one's neighbor. Honor is the social witness given to human dignity, and everyone enjoys a natural right to the honor of his name and reputation and to respect. Thus, detraction and calumny offend against the virtues of justice and charity.
"False & malicious misrepresentation of the words or actions of others, calculated to injure their reputation" [Fowler], mid-15c., from Middle French calomnie (15c.), from Latin calumnia "trickery, subterfuge, misrepresentation, malicious charge," from calvi "to trick, deceive," from PIE root *kel- (6) "to deceive, confuse" (cognates: Greek kelein "to bewitch, seduce, beguile," Gothic holon "to deceive," Old Norse hol "praise, flattery," Old English hol "slander," holian "to slander").
1805, "cask of drinking water kept on a ship's deck, having a hole (scuttle) cut in it for a cup or dipper," from scuttle "opening in a ship's deck" + butt "barrel." Earlier scuttle cask (1777). Meaning "rumor, gossip" first recorded 1901, originally nautical slang, traditionally said to be from the sailors' custom of gathering around the scuttlebutt to gossip. Compare water-cooler, figurative for "workplace gossip" mid-20c.
mid-15c., from Old French maledicion "a curse" (15c.), from Latin maledictionem (nominative maledictio) "the action of speaking evil of, slander," in Late Latin "a curse," noun of action from past participle stem of maledicere "to speak badly or evil of, slander," from male "badly" + dicere "to say".
c.1300, "formal written statement," especially, in civil law, "plaintiff's statement of charges" (mid-14c.); from Old French libelle (fem.) "small book; (legal) charge, claim; writ; written report" (13c.), from Latin libellus "a little book, pamphlet; petition, written accusation, complaint," diminutive of liber "book". Broader sense of "any published or written statement likely to harm a person's reputation" is first attested 1630s.
Definitions are from the Online Etymology Dictionary.