Turning the other cheek in the old Scripture
Celsus, then, without setting the passages from the Law that seem contrary beside those from the Gospel, also says this: “to let the man who has struck once strike again.” We shall reply that we know the saying “An eye for an eye and a tooth for a tooth,” spoken to the men of old (Matthew 5:38; Exodus 21:24), and that we have also read “But I say to you” (Matthew 5:39): “To the one who strikes you on the cheek, offer the other also” (Luke 6:29).
But since Celsus, I think, has had his ears filled by those who divide the deity of the Gospel from the deity of the Law, and so puts forward such things, we must say in answer to his argument that the old writings too know the saying “To the one who strikes you on the right cheek, offer the other also” (Matthew 5:39). At any rate, it is written in the Lamentations of Jeremiah: “It is good for a man when he bears a yoke in his youth. He will sit alone and keep silent, because he has taken it upon himself. He will give his cheek to the one who strikes him, and he will be filled with reproaches” (Lamentations 3:27–28, 30).
The Gospel of God does not issue orders contrary to the God of the Law, not even about the blow on the cheek taken literally. Neither of the two is lying, neither Moses nor Jesus; nor did the Father, in sending Jesus, forget what he had commanded Moses; nor indeed did he condemn his own laws, change his mind, and send his messenger for the opposite purpose.
Greek
Ὁ μὲν οὖν Κέλσος, μὴ ἀντιπαραθεὶς τὰ δοκοῦντα ἐναντία ἀπὸ τοῦ νόμου τοῖς ἀπὸ τοῦ εὐαγγελίου, φησὶ καὶ τό· τῷ δ᾿ ἅπαξ τυπτήσαντι παρέχειν καὶ αὖθις τύπτειν. ἡμεῖς δ᾿ ἐροῦμεν εἰδέναι μὲν καὶ τὸ „ὀφθαλμὸν ἀντὶ ὀφθαλμοῦ καὶ ὀδόντα ἀντὶ ὀδόντος“ εἰρημένον τοῖς πάλαι ἀνεγνωκέναι δὲ καὶ τὸ „ἐγὼ δὲ λέγω ὑμῖν“· „τῷ τύπτοντί σε εἰς τὴν σιαγόνα πάρεχε καὶ τὴν ἄλλην.“ ἀλλ᾿ ἐπεὶ περιηχηθεὶς οἶμαι ὁ Κέλσος ἀπὸ τῶν διαιρούντων τὴν κατὰ τὸ εὐαγγέλιον θεότητα ἐκ τῆς νομικῆς θεότητος τὰ τοιαῦτα τίθησι, λεκτέον πρὸς τὸν λόγον αὐτοῦ ὅτι οἶδε καὶ τὰ παλαιὰ γράμματα (τὸ) „τῷ τύπτοντί σε εἰς τὴν δεξιὰν σιαγόνα πάρεχε καὶ τὴν ἄλλην.“ ἐν γοῦν τοῖς Ἱερεμίου Θρήνοις γέγραπται· „ἀγαθὸν ἀνδρὶ, ὅταν ἄρῃ ζυγὸν ἐν νεότητι αὐτοῦ, καθήσεται κατὰ μόνας καὶ σιωπήσεται, ὅτι ἦρεν ἐφ᾿ ἑαυτῷ. δώσει τῷ παίοντι αὐτὸν σιαγόνα, καὶ χορτασθήσεται ὀνειδισμῶν.“ οὐκ ἀντιδιατάσσεται θεοῦ τὸ εὐαγγέλιον τῷ τοῦ νόμου θεῷ οὐδὲ περὶ τῆς κατὰ τὸ ῥητὸν κατὰ κόῤῥης πληγῆς· οὐδ᾿ ὁπότερος ψεύδεται, οὔτε Μωϋσῆς οὔτε Ἰησοῦς, οὐδ᾿ ὁ πατὴρ τὸν Ἰησοῦν πέμπων ἐπελάθετο, τίνα Μωϋσεῖ διετάξατο· ἀλλ᾿ οὐδὲ καταγνοὺς τῶν ἰδίων νόμων μετέγνω καὶ τὸν ἄγγελον ἐπὶ τοῖς ἐναντίοις ἀποστέλλει.