The Iliad 24.139–140

if verily with full purpose of heart the Olympian himself so biddeth.

τῇδʼ εἴη· ὃς ἄποινα φέροι καὶ νεκρὸν ἄγοιτο, εἰ δὴ πρόφρονι θυμῷ Ὀλύμπιος αὐτὸς ἀνώγει.