Gen 6:3: "my spirit shall not …" and the 120 years

Says לֹא־יָדוֹן רוּחִי בָאָדָם לְעֹלָם: "my spirit shall not … in man forever." OSHB tags יָדוֹן as a Qal imperfect under H1777, for which BDB gives "act as judge, minister judgment," "plead the cause," "govern," and "he cannot contend with one mightier than he." The BSB has "contend"; Swete has Οὐ μὴ καταμείνῃ, "shall not remain," and adds τούτοις, "these"; the BSB's footnote gives the Greek "remain." Then בְּשַׁגַּם, which OSHB divides as preposition, relative and particle ("in that also"), with הוּא בָשָׂר, "he is flesh" ("for he is mortal," BSB; BDB on the noun, "man over against God as frail or erring"). Last, וְהָיוּ יָמָיו מֵאָה וְעֶשְׂרִים שָׁנָה, "and his days shall be a hundred and twenty years"; Swete ἑκατὸν εἴκοσι ἔτη.

Implies As tagged, the verb belongs with judging and contending; "remain" is the Greek's sense, which BDB's outline of this root does not list.

Uncertain What the 120 years measure. (1) A limit on a human life: ground, "his days" is said of a lifetime; objection, several lives after the flood in Genesis are longer. (2) The time left before the flood: ground, the sentence heads the flood account; objection, 5:32 ("After Noah was 500 years old") and 7:6 ("Noah was 600 years old when the floodwaters came") stand 100 years apart, not 120; reply, 6:3 is not dated and need not follow 5:32 in time. No lean is taken here.