aletheia is the truth known, received, taught, and lived in faithful speech and conduct.

The dominant use presents truth as a received and known reality that can be taught, spoken, upheld, believed, opposed, or abandoned. It also describes truthful speech set against lying and a manner of conduct in which love, obedience, and walking accord with that truth.

1. Truth as a known and upheld message · dominant

   The noun identifies what people come to know, receive, believe, or resist: 1 Timothy 2:4 speaks of coming to its knowledge, 2 Thessalonians 2:10 of receiving its love, and 2 Timothy 4:4 of turning away from listening to it. In 2 Timothy 2:15 the genitive singular form qualifies “word,” while 1 Timothy 3:15 calls the assembly a pillar and foundation of it; in 2 Timothy 2:18 others have deviated concerning it.

   1 Timothy 2:42 Thessalonians 2:102 Timothy 2:151 Timothy 3:152 Timothy 2:182 Timothy 4:4
2. Truthfulness contrasted with false speech · common

   In 1 John 2:21 the clause contrasts the accusative and genitive forms with a lie that does not come from it. The accusative singular occurs where Paul says he will speak truthfully in 2 Corinthians 12:6, and Ephesians 4:25 places speaking it with one’s neighbor beside putting off falsehood. In Acts 26:25 the APB renders Paul’s words as “true and rational words.”

   1 John 2:212 Corinthians 12:6Ephesians 4:25Acts 26:25John 16:72 Corinthians 7:14
3. Truth embodied in conduct and love · occasional

   The dative singular form appears in calls to action: 1 John 1:6 contrasts walking in darkness and lying with practicing it, and 1 John 3:18 contrasts love merely in word or tongue with love in work and truth. In 2 John 1:4 and 3 John 1:4, people are described as walking in it in connection with the Father’s commandment and the writer’s joy; Galatians 2:14 measures conduct by the truth of the gospel.

   1 John 1:61 John 3:182 John 1:43 John 1:4Galatians 2:141 Peter 1:22

In the Anselm Project Bible: Across these verses the APB commonly uses “truth,” including “knowledge of the truth,” “word of truth,” and “walking in the truth.” It also renders clauses with “true,” “truly,” and “what is true”; These English choices do not by themselves define the noun.