ἦν vs ἐγένετο: being and becoming in the prologue

Says The prologue sets the imperfect of εἰμί against aorist forms of γίνομαι. The Word "was" (ἦν, ēn: 1:1–2, 4, 9–10). TAGNT codes it V-IAI-3S, and per Style Guide §12.2 we keep TAGNT's code. Created things "came to be" (ἐγένετο, egeneto: 1:3, 10), and John the Baptist "came" (1:6, Ἐγένετο ἄνθρωπος). At the incarnation the Word "became flesh" (1:14, σὰρξ ἐγένετο).

Says ἐν ἀρχῇ (en archē, "in the beginning") echoes Gen 1:1 LXX. At the point where creation begins, the Word already was. No beginning is stated for him.

Implies The contrast teaches that the Word exists uncreated and that everything else has a beginning through him (1:3). In 1:14 he took on a new mode of existence without ceasing to be what 1:1 says he was. Compare John 8:58, which contrasts γενέσθαι (Abraham) with ἐγώ εἰμι (Jesus).

Caution: The imperfect tense alone does not prove eternity. Aspect presents an action as ongoing; it does not measure duration. The argument rests on the contrast in context and on the Genesis echo, not on the tense form alone. The Hebrew Scholar's notes cover the Gen 1:1 background.