Psalm 78/Notes/Grammar.V. 34.837458
From Psalms: Layer by Layer
v. 34 – For the compound predicate interpretation, see the discussion of the multi-verb predication at phrase level (as attested, e.g., in the NJPS: "and sought God once again" cf. LUT, NABRE, NIV, RVC). For the waw-coordination in a serial verb construction, see further, the note at v. 6. Here, וְ֝שָׁ֗בוּ contributes the aspectual value of habituality/repetition (Aikhenvald 2018, 6). cf. the similar case in v. 41. Alternatively, וְ֝שָׁ֗בוּ could be considered its own event, i.e., turning back (as the ancient versions and the ESV's " they repented and sought God earnestly").
For the alternative preposition אֵלָיו in place of the the MT's object אֵל "God," see the Syr. ܠܘܬܗ "to him" (cf. the NIV's "they eagerly turned to him again").