ᾔδεμεν

From LSJ

πάντες γὰρ οἱ λαβόντες μάχαιραν ἐν μαχαίρῃ ἀπολοῦνται → all they that take the sword shall perish with the sword

Source

French (Bailly abrégé)

1ᵉ pl. pqp. de *εἴδω.