It consist of self-witness presented in two steps:
- What he is not (negative).
- What he is (positive).
This is followed by witness to Christ.
The call begins with the response of two disciples of John the Baptist following Jesus. One of them gives witness and others follow. Thus a chain action of call and witness is reported. Through this a progressive revelation of the identity of Jesus is realized in the proclamation made by those who have been called and those who give witness.
John the Baptist is witness according to Gospel of John and not a preacher as in the Synoptic Gospels (Mk 1: 4-8; Mt 3: 1-12; Lk 3: 1-20). The evangelist has introduced John the Baptist as a testimony already in the prologue (Jn 1: 6-8, 15). Now the delegation from Jerusalem questions John the Baptist regarding his identity. Negatively, John the Baptist univocally denies that he is Christ (Is 61: 1f), that he is Elijah to come (Mal 4: 5; Sir 48: 10) and that he is the prophet (Deut 18: 15, 18). These are the three types of the messianic expectations of Israel. Positively, John the Baptist identifies himself as “a voice crying” in the wilderness” (Is 40: 3). This identification agrees with the Synoptic picture. Isaiah 40: 3 is a common source (Mk 1: 2-3; Mt 3: 3; Lk 3: 4). When John the Baptist denies that he is Elijah, it seems to contradict the Synoptic vision concerning John the Baptist that he is Elijah to come (Mt 11: 14; 17: 9-13). However a distinction of the speakers – Jesus in Synoptic Gospels and John the Baptist in the Gospel of John – explains it. John the Baptist’s self-consciousness expressed in the Gospel of John need not include the interpretation given by Jesus to John the Baptist’s mission in the Synoptic tradition. Thus John the Baptist is very conscious of who he is not and who he is. This is a basic preparation for witnessing to Christ.