Origen of Alexandria, Against Celsus 35
Lest we appear to be offering consolation drawn from the Hebrew tongue to those who do not grasp it — whether they agree with it or not — let us instead find our comfort in the very wording of the prophecy: that the prophet said this one would be born of a virgin, and that on his birth the name 'God with us' is bestowed (Isaiah 7:14). Scripture records that the Lord said to Ahaz, 'Ask a sign for yourself from the Lord your God, whether in the depth or in the height' (Isaiah 7:11), and the sign given immediately follows: 'Behold, the virgin shall conceive and bear a son.' What sort of sign would it be for a young woman, not a virgin, to give birth? And to whom does it more fittingly belong to bear 'Emmanuel' — that is, 'God with us' — a woman who has known intercourse and conceived through human passion, or one who remains pure, holy, and a virgin? For it is fitting for such a one to bear the offspring upon whose birth the words 'God with us' are declared. But if someone tries to rationalize by insisting the promise was spoken to Ahaz — 'Ask a sign for yourself from the Lord your God' — we will answer: in the days of Ahaz, who was born, upon whose birth the name 'Emmanuel, which is God with us,' is pronounced? If no one is found, then clearly what was said to Ahaz was addressed to the house of David, because the Savior is written to have been born 'according to the flesh' from the seed of David (Isaiah 7:14). Moreover, this 'sign' is said to reach 'into depth or into height,' since 'he who descended is also he who ascended above all the heavens, that he might fill all things' (Ephesians 4:10). I speak these things as one addressing a Jew who accepts the prophecy. Let Celsus, or anyone allied with him, declare: with what mind does the prophet speak of future things — whether these or others recorded in the prophecies? Is it a foreknowing mind, or not? For if it is a foreknowing mind, the prophets possessed a divine spirit; if not, let him explain the mind of the one who dares to speak of the future and is admired among the Jews for prophecy.
Greek
Ἵνα δὲ μὴ δοκῶμεν ἀπὸ λέξεως Ἑβραϊκῆς τοῖς μὴ καταλαμβάνουσι, πότερον συγκαταθετέον αὐτῇ ἢ μὴ, φέρειν παραμυθίαν περὶ τοῦ προφήτην εἰρηκέναι ἐκ παρθένου τεχθήσεσθαι τοῦτον, ἐφ᾿ οὗ τῇ γενέσει λέλεκται τὸ „μεθ᾿ ἡμῶν ὁ θεὸς“, φέρε ἐπ᾿ αὐτῆς τῆς λέξεως παραμυθησώμεθα τὸ λεγόμενον. ὁ μὲν κύριος ἀναγέγραπται εἰρηκέναι τῷ Ἄχαζ· „αἴτησαι σεαυτῷ σημεῖον παρὰ κυρίου τοῦ θεοῦ σου εἰς βάθος ἢ εἰς ὕψος,“ ἑξῆς δὲ τὸ διδόμενον σημεῖον τὸ „ἰδοὺ ἡ παρθένος ἐν γαστρὶ ἕξει καὶ τέξεται υἱόν.“ ποῖον οὖν σημεῖον τὸ νεάνιδα, μὴ παρθένον τεκεῖν; καὶ τίνι μᾶλλον ἁρμόζει γεννῆσαι „Ἐμμανουὴλ,“ τουτέστι „μεθ᾿ ἡμῶν ὁ θεὸς,“ ἆρα γυναικὶ συνουσιασθείσῃ καὶ διὰ πάθους γυναικείου συλλαβούσῃ ἢ ἔτι καθαρᾷ καὶ ἁγνῇ καὶ παρθένῳ; ταύτῃ γὰρ πρέπει γεννᾶν γέννημα, ἐφ᾿ ᾧ τεχθέντι λέγεται τὸ „μεθ᾿ ἡμῶν ὁ θεός.“ ἐὰν δὲ καὶ οὕτως εὑρεσιλογῇ λέγων ὅτι τῷ Ἄχαζ εἴρηται· „αἴτησαι σεαυτῷ σημεῖον παρὰ κυρίου τοῦ θεοῦ σου,“ ἀπαντήσομεν· κατὰ τοὺς χρόνους τοῦ Ἄχαζ τίς ἐγεννήθη, ἐφ᾿ οἷ τῇ γενέσει λέγεται τὸ „Ἐμμανουὴλ, ὅ ἐστι μεθ᾿ ἡμῶν ὁ θεός,·“ εἰ γὰρ οὐδεὶς εὑρεθήσεται, δηλονότι τὸ τῷ Ἄχαζ εἰρημένον τῷ οἴκῳ εἴρηται Δαυὶδ διὰ τὸ „ἐκ σπέρματος Δαυὶδ“ ἀναγεγράφθαι τὸν σωτῆρα γεγονέναι „τὸ κατὰ σάρκα“· ἀλλὰ καὶ τὸ „σημεῖον“ τοῦτο „εἰς βάθος ἢ εἰς ὕψος“ λέγεται εἶναι, ἐπεὶ „ὁ καταβὰς οὗτός ἐστι καὶ ὁ ἀναβὰς ὑπεράνω πάντων τῶν οὐρανῶν, ἵνα πληρώσῃ τὰ πάντα.“ ταῦτα δὲ λέγω ὡς πρὸς τὸν Ἰουδαῖον συγκατατιθέμενον τῇ προφητείᾳ. λεγέτω δὲ καὶ Κέλσος ἤ τις τῶν σὺν αὐτῷ, ποίῳ νῷ ὁ προφήτης περὶ μελλόντων ἢ ταῦτα ἢ ἕτερα λέγει, ὁπόσα ἀναγέγραπται ἐν ταῖς προφητείαις· ἆρα γὰρ προγνωστικῷ μελλόντων ἢ οὔ; εἰ μὲν γὰρ προγνωστικῷ μελλόντων, θεῖον εἶχον πνεῦμα οἱ προφῆται· εἰ δ᾿ οὐ προγνωστικῷ μελλόντων, παραστησάτω τὸν νοῦν τοῦ ἀποτολμῶντος καὶ λέγοντος περὶ μελλόντων καὶ θαυμαζομένου παρὰ τοῖς Ἰουδαίοις ἐπὶ προφητείᾳ.