orally
From LSJ
ἵνα οὖν μηδ' ἐν τούτῳ δῷ αὐτοῖς λαβήν (Photius, Fragments on the Epistle to the Romans 483.26) → so that he doesn't give them even here a handle (= an opportunity for refutation)
English > Greek (Woodhouse)
adverb
by word of mouth: P. ἀπὸ στόματος, P. and V. ἀπὸ γλώσσης.
by hearsay: P. ἀκοῇ.