Proverbs 10:20 New English Translation

²⁰What the righteous say^[a] is like^[b] the best^[c] silver,
but what the wicked think^[d] is of little value.^[e]

Proverbs 10:20 tn Heb “the lips of the righteous.” The term “lips” functions as a metonymy of cause for speech. This contrasts the tongue (metonymy of cause for what they say) with the heart (metonymy of subject for what they intend). What the righteous say is more valuable than what the wicked intend.
Proverbs 10:20 tn The comparative “like” is not in the Hebrew text but is implied by the metaphor; it is supplied in the translation for the sake of clarity.
Proverbs 10:20 tn Or “pure”; Heb “choice.”
Proverbs 10:20 tn Heb “the heart of the wicked” (so KJV, NAB, NIV). The term “heart” functions as a metonymy of cause for thoughts. The term לֵב (lev, “heart”) often refers to the seat of thoughts, will and emotions (BDB 524 s.v. 3-4).
Proverbs 10:20 tn Heb “like little.” This expression refers to what has little value: “little worth” (so KJV, NAB, NRSV; cf. BDB 590 s.v. מְעַט 2.d). The point of the metaphor is clarified by the parallelism: Silver is valuable; the heart of the wicked is worth little. Tg. Prov 10:20 says it was full of dross, a contrast with choice silver.

New English Translation (NET)