Son of His People
It is above all by virtue of its historical origin that the Christian community discovers its links with the Jewish people. Indeed, the person in whom it puts its faith, Jesus of Nazareth, is himself a son of this people. So too are the Twelve whom he chose “to be with him and to be sent out to proclaim the message” (Mk 3:14). In the beginning, the apostolic preaching was addressed only to the Jews and proselytes, pagans associated with the Jewish community (cf. Ac 2:11). Christianity, then, came to birth in the bosom of first century Judaism…
A perennial manifestation of this link to their beginnings is the acceptance by Christians of the Sacred Scriptures of the Jewish people as the Word of God addressed to themselves as well. 
– Because of this, those who consider mere cultural facts contingent that Jesus was Jewish and that it environment outside the Jewish world – information that they think that can be replaced by another religious tradition without the person of the Jesus lost his identity – these people not only unknown the meaning of history of salvation, but radically attack the real truth of the Incarnation, thus making impossible an authentic inculturation.
. The Pontifical Biblical Commission, The Jewish People and Their Sacred Scriptures in the Christian Bible (2002), nº 2.
. Pope John Paul II to a Symposium on the Roots of Anti-Judaism, Friday, 31 October 1997.