οἷον, acc., is object to φωνῆσαι only, but exerts a causal force over ἀποστρέψαι also (as “ὥστε” would have done): the first οὐδ᾽=“"not even,"” the second links the two infinitives:—“"such that 'tis not lawful even to utter it to any of my comrades, or to turn them back."” The utterance would turn them back: but the curse is too dreadful to be revealed. ἀλλ᾽ ὄντ̓: sc. “δεῖ”, evolved from the negative οὐδ᾽ ἔξεστι: cp.
.“ὃν μὴ ξένων ἔξεστι μηδ᾽ ἀστῶν τινι
δόμοις δέχεσθαι, …
ὠθεῖν δ᾽ ἀπ᾽ οἴκων
”
