The title "Christ" was applied to Jesus of Nazareth because he fulfilled Old Testament prophecies about the coming Messiah.
The prophets previewed Jesus as the Messiah (Psa. 2:1ff; Dan. 9:25-27). He affirmed that he was the promised Christ (Jn. 4:25-26; Mk. 14:61-62). Because of his miracles and teaching, the disciples became convinced he was the Christ (Mt. 16:16). Even many of those involved in his crucifixion believed he was the Messiah (see Acts 2:29ff).
There is no legitimate reason today for any Jewish person to reject Jesus of Nazareth as the promised Messiah of Old Testament literature. Only bias obscures their vision of the evidence (2 Cor. 3:14ff).