[Tzfat]

The problem is, Christianity and Judaism both teach that a Jew that converts to Christianity is no longer a Jew. This is not biblical. the Catholic Church, by acknowledging that Jews should remain Jews is at least semantically correct.

[Yaelle]

Judaism does NOT teach that a Jew becoming a Christian is not a Jew. A Jew stays a Jew, to us.

[circlecity]

"The problem is, Christianity and Judaism both teach that a Jew that converts to Christianity is no longer a Jew."

That's not true at all. All of the first Christians were Jews. Paul after he became a Christian still considered himself a Jew. Of the tribe of Benjamin. Messianic Jews consider themselves Jewish Christians. Jesus was a Jewish Christian.