Proverbs 27:6 New English Translation

⁶Faithful^[a] are the wounds of a friend,
but the kisses^[b] of an enemy are excessive.^[c]

Proverbs 27:6 tn The Niphal participle of אָמַן (ʾaman) means “faithful; reliable; sure; trustworthy.” The word indicates that the wounds from a friend “can be trusted” (so NIV, NCV) because they are meant to correct and not to destroy (e.g., 25:12; Deut 7:9; Job 12:20).
Proverbs 27:6 sn “Kisses” probably represents a metonymy of adjunct; the term describes any expressions or indications of affection. But coming from an enemy, they will be insincere—as indicated by their excessive number.
Proverbs 27:6 tn The form is נַעְתָּרוֹת (naʿtarot), the Niphal participle of עָתַר (ʿatar, “to be abundant”). Contemporary translations render this rare form in a number of different ways: “deceitful” (NASB, NKJV); “profuse” (NRSV); “many” (NLT). But the idea of “excessive” or “numerous” fits very well. The kisses of an enemy cannot be trusted, no matter how often they are presented.

New English Translation (NET)