ἐάν τις θέλῃ τὸ θέλημα αὐτοῦ ποιεῖν, γνώσεται περὶ τῆς διδαχῆς, πότερον ἐκ τοῦ Θεοῦ ἐστιν ἢ ἐγὼ ἀπ᾽ ἐμαυτοῦ λαλῶ.