John 1:6

In this verse John passes to the historical; and like the other evangelists begins with the Baptist. So Theodore Mops: μετεληλυθὼς ἐπὶ τὴν ἐπιφάνειαν τοῦ υἱοῦ, τίνα ἄν εὗρεν ἀρχὴν ἑτέραν ἤ τὰ κατὰ τὸν Ἰωάννην; ἐγένετο ἄνθρωπες, “not there was (chap. John 3:1), but denoting the appearing, the historical manifestation,” Meyer. Cf. Luke 1:5. The testimony of John is introduced not only as a historical note but in order to bring out the aggravated blindness of those who rejected Christ. This man was ἀπεσταλμένος παρὰ θεοῦ. Holtzmann says “an historical appearance is characterised as Godsent”. It might rather be said that an historical appearance sent to fulfil a definite Divine purpose is so characterised. There is no designation our Lord more frequently applies to Himself. In the prayer of chap. 17. some equivalent occurs six times. And in the epistle to the Hebrews He is called “the Apostle of our confession”. No distinguishing title is added to the common name “John”, Westcott says: “If the writer of the Gospel were himself the other John of the Gospel history, it is perfectly natural that he should think of the Baptist, apart from himself, as John only”. Watkins says: “The writer stood to him in the relation of disciple to teacher. To him he was the John.” Afterwards the disciple became the John.