1 John 3:18 New English Translation

¹⁸Little children, let us not love with word or with tongue but in deed and truth.^[a]

1 John 3:18 sn The noun truth here has been interpreted in various ways: (1) There are a number of interpreters who understand the final noun in this series, truth (ἀληθείᾳ, alētheia) in an adverbial sense (“truly” or “in sincerity”), describing the way in which believers are to love. If the two pairs of nouns are compared, however, it is hard to see how the second noun with tongue (γλώσσῃ, glōssē) in the first pair can have an adverbial sense. (2) It seems better to understand the first noun in each pair as produced by the second noun: Words are produced by the tongue, and the (righteous) deeds with which believers are to love one another are produced by the truth.

New English Translation (NET)