27 The form תַּלְשֵׁן (talshen) is the Hiphil jussive (with the negative אַל, ’al); it is a denominative verb from the noun “tongue” (Heb “wag the tongue”). It means “to defame; to slander,” if the accusation is untrue. Some have suggested that the word might have the force of “denouncing” a slave to his master, accusing him before authorities (e.g., Deut 23:15–16). This proverb would then be a warning against meddling in the affairs of someone else.
28 If what was said were true, then there would be no culpability. But the implication here is that it was slander. And the effect of that will be a curse—the person who is the target of the slander will “curse” the person who slandered him (קָלַל [qalal] in the Piel means “to treat lightly [or, with contempt]; to curse”), and culpability will result (the verb וֹשׁם means “to be guilty; to make a guilt offering [or, reparation offering]”). This word for guilt suggests a connection to the Levitical teaching that the guilty had to make reparation for damages done (Lev 5). Cf. “you will have to pay the penalty”; , “you will pay for it.”
29 The next four verses all start with the Hebrew expression translated “There is a generation.” This is a series of denunciations of things that are dangerous in society without mentioning specific punishments or proscriptions. The word “generation” as used in this passage refers to a class or group of people.
30 The first observation is that there is a segment in society that lacks respect for parents. This uses the antonyms “curse” and [not] “bless” to make the point. To “curse” a parent could include treating them lightly, defaming them, or showing disrespect in general. To “bless” would mean to honor, respect, or enrich in some way, which is what should be done (e.g., Exod 21:17; Prov 20:20).