How can the gospel of John be called anti semitic when Jesus and his disciples were all Jews?

Answer:

The author of the Gospel of John clearly places himself, and those whom he represents, as separated from the Jews. He speaks of "the Passover of the Jews" (John 2:13, 6:4, 11:55), the religious rules of the Jews about purification (John 2:6), a religious festival of the Jews (John 5:1), the Festival of Tabernacles of the Jews (John 7:2), the Day of Preparation of the Jews (John 19:42), and the way in which Jews prepare a body for burial (John 19:40).

And quite as clearly he regards Jesus as not "a Jew." In talking to the Jews, Jesus speaks of "your Law" (John 7:19, 8:17, 10:34) and "your circumcision" (John 7:22). Abraham is "your father" (John 8:56). When the Jews say to him, "Our ancestors ate manna in the desert" (John 6:31), Jesus replies, "What Moses gave you was not the bread from heaven" (John 6:32), and later on says, "Your ancestors ate the manna in the desert" (John 6:49).

It is true that twice Jesus is called a Jew: by the Samaritan woman (John 4:9) and by Pilate (John 18:35). But in both instances the term is used in its sense of "person of Judah," contrasted with the Samaritan and the Roman. The same applies in John 4:22, where Jesus says to the Samaritan woman, "You [Samaritans] do not really know whom you worship; we [Jews] know whom we worship, for salvation is from the Jews." For John’s Jesus, "Salvation is from the Jews" does not refer to the Jewish people per se. "Salvation" is now the inheritance of the true worshiper of God as defined by Jesus (John 4:23).

Apart from those two instances, it is only in John 1:11 that Jesus is identified as a Jew, in the statement that he comes to "his own country," but "his own people" did not receive him. This passage, however, does not go against the Gospel as a whole, in which Jesus is shown as not being a part of "the Jews." Jesus appears as no longer a member of the Jewish people or its religion but speaks to the Jews as if he were a non-Jew. The Fourth Gospel is not about a Jew or written for Jews and expresses contempt for Jews and Judaism.

Source: http://www.jewsforjudaism.org/knowledge/how_can_the_gospel_of_john_be_called_anti_semitic_when_jesus_and_his_disciples_were_all_jews_/