Psalm 2/Notes/Grammar.v. 1.155802
The noun רִיק could either be the direct object of the verb[1] or a nominal adverb.[2] Both interpretations are grammatically possible. For the direct object interpretation, cf. Ps 4:3 (תֶּאֱהָב֣וּן רִ֑יק). See also the numerous examples of הגה taking a similar abstract noun as its object: Isa 59:3 (עַוְלָה); Ps 37:30 (חָכְמָה); Ps 38:13 (וּמִרְמֹות); Prov 8:7 (אֱמֶת); Job 27:4 (רְמִיָּה). For the nominal adverb interpretation, cf. Ps 73:13—אַךְ־רִ֭יק זִכִּ֣יתִי לְבָבִ֑י (also Isa 30:7; cf. the frequently occurring phrase לְרִיק/לָרִיק, Lev 26:16, 20; Isa 49:4; 65:23; Job 39:16). Given the fact that the verb הגה typically takes an object (either a bare noun phrase or a beth prepositional phrase), the direct object interpretation is more likely. If the poet wanted to clearly indicate an adverbial reading, we might have expected לריק.