Antichrist, Devil, Satan

Πάς γὰρ ὃς ἂν μὴ ὁμολογῇ Ἰησοῦν Χριστὸν ἐν σαρκὶ ἐληλυθέναι, ἀντιχριστός ἐστιν· καὶ ὃς ἂν μὴ ὁμολογῇ τὸ μαρτύριον τοῦ σταυροῦ, ἐκ τοῦ διαβόλου ἐστιν· καὶ ὃς ἂν μεθοδεύῃ τὰ λόγια τοῦ κυρίου πρὸς τὰς ἰδίας ἐπιθυμίας καί λεγῃ μήτε ἀνάστασιν μήτε κρίσιν, οὖτος πρωτότοκός ἐστι τοῦ σατανᾶ. διὸ ἀπολιπόντες τὴν ματαιότητα τῶν πολλῶν καὶ τὰς ψευδοδιδασκαλίας ἐπὶ τὸν ἐξ ἀρχῆς ἡμῖν παραδοθέντα λόγον ἐπιστρέψωμεν, νήφοντες πρὸς τὰς εὐχὰς καὶ προσκαρτεροῦντες νηστείας, δεήσεσιν αἰτούμενοι τὸν παντεπόπτην θεὸν μὴ εἰσενεγκειν ἡμας εἰς πειρασμόν. Ἅγιος Πολύκαρπος Σμύρνης, Πρὸς Φιλιππήσιους Έπιστολή Source: Migne PG 5.1012b

Everyone who does not confess Jesus Christ is come in the flesh is Antichrist; he who does not confess the witness of the cross is of the Devil; and he who perverts the words of the Lord to suit his own desires and says there is neither resurrection nor judgement, this man is the first born of Satan. So being done with these inanities of the mob, these false teachings, let us turn back to the word given to us in the beginning, sober in prayer and strong in fasting, asking the all seeing God not to lead us into temptation. Saint Polycarp of Smyrna, Letter to the Phillipians.