Knowledge and the Deed

Οὐ ῥημάτων ἀπαγγελία, ἀλλὰ πραγμάτων διακονία τὸν τῆς θείας παιδεύσεως ζηλωτὴν ἀποφαίνει. Ούδὲ γὰρ ὁ ἀρχαῖος ἀντάρτης, ἐπειδὴ τῶν θείων χρησμῶν ἐμέμνητο πειράζων τὸν Κύριον ἐπαινετὸς ἧν ἄρα τῆς τούτων μαθήσεως, ἀλλ' ἀπόκριτος καὶ ἀπόβλητος, ὅτι τὴν γνῶσιν ἔχων, τὴν πρᾶξιν ἀρνεῖται. Εἰ τοίνυν μὴ κοῦφος φαίνεσθαι βούλει, καὶ ἐπὶ γλώττης μόνης ἔχων τὴν παίδευσιν, ἔργῳ ἐπίδειξον ταύτην. Οὐδὲ γὰρ τῆς ἔξωθεν ὁπλοφορίας ὁ Γολιὰθ ἀπώνατοτι, τοῖς ἔξωθεν ἀσθενῶν βοηθήμασιν. Ἅγιος Ἰσίδωρος Του Πηλουσιώτου, Βιβλίον Πρῶτον, ΡΠ', Θεοφρονιω

Not the enunciation of words but attention to deeds is the revelation of fervour for Divine education. For neither the old rebel, on account of that Divine saying he held in his mind when he tested the Lord,1 was found praiseworthy because of his learning, but in answer he received rejection. For though he possessed knowledge action he corrupted. If then a man does not wish to appear a vacuous fellow, having learning only on the tongue, show it by the deed. Goliath's external trappings did not benefit him but rather by such he was made weak. 2 Saint Isidore of Pelusium, Book 1, Letter 180, To Theophronius  1 Mt 4 2 I Kings 17