Psalm 92/Notes/Grammar.V. 8a.807067
v. 8a – The second infinitival clause representing the verb צוץ in Symmachus' ܘܟܕ ܡܗ̈ܒܒܝܢ ("and when they flourish") is insightful for the intended meaning (see the [issue]), but is unlikely a morphological variant, and has thus not been included as a valid alternative. See also the attempt in Hebr. to level the syntax of the two clauses with two finite verbs (germinaverunt impii quasi faenum et floruerunt omnes qui operantur iniquitatem ut contererentur usque in sempiternum), which cannot be derived textually from בִּפְרֹ֤חַ.
For the elided subject, see also Job 27:14: ø אִם־יִרְבּ֣וּ בָנָ֣יו לְמוֹ־חָ֑רֶב "If his children are multiplied, it is for the sword" (ESV); cf. Saadia's פאנה (Kafaḥ 1966, 213) >> זאֹת הָֽיְתָה (Delitzsch 1877, 68) "this was/is"; Ḥakham's (1979, 181) משׁמעות תאור הפעלה ... זוֹ "the sense of the description of the action... this"; Rashi, however, considers a nominal form of "their flourishing" to be the subject (שהפרחת' אינה אלא להשמידם).