Here is a link to a 1998 interview with Jacques Doukhan by John Graz; it was published in Ministry Magazine. There are some very significant ideas here— I recommend a careful reading.
Christians and Jews: Mission impossible?
The first question that John Graz asks Jacques Doukhan is whether his life's mission, the promotion of better understanding between Christians and Jews, is a “Mission Impossible”. Dr. Doukhan begins by saying “I don't know”— it seems almost freudian— perhaps revealing that there might be occasional moments of discouragement at the daunting challenges of this mission. Yet he retains a “profound conviction” in a “destiny” of Jewish-Christian reconciliation.
Dr. Doukhan frames the issue of a Christian “conversion”— meaning a repentance from anti-Jewish beliefs and attitudes— in salvational terms. As this is a topic that I have studied for some time I affirm the significance of this issue, but I suspect that most Seventh-day Adventists would, on giving it serious thought, find it a little shocking. The following to paragraphs from the interview get to the heart of the issue.
To hope for a reconciliation after Auschwitz amounts then to hope in a genuine "conversion" on the part of the Christians. As long as Christians will not take this sin of anti-Semitism seriously, as long as they are not ready to turn back, repent, and recognize the Jewish roots that bear them, there is no hope for reconciliation. As a result, we can even say that there is no hope for any other reconciliation, and I mean here especially the Christian reconciliation with the God of Israel Himself.
The relation between the two connections is such that a Christian theologian has gone so far as to denounce anti-Semitism as a sin against the Holy Spirit, i.e., an unforgivable sin. This may sound exaggerated for many who have not come to comprehend the hideous nature of this sin and its implications, and that's simply because they have gotten so used to it.
It is in the paragraphs just before these intense statements that Dr. Doukhan touches on the beliefs that are the seeds of this anti-Semitism.
Meanwhile, there is the supersession theology, which denies the Jews and Israel the right even to be Israel, since the "true Israel" is another people. (This theory has been denounced as "a spiritual holocaust.")
On the topic of Christian outreach— mission— to the Jewish people, Dr. Doukhan advises that we re-frame this in a way that may be completely unfamiliar.
Christians who want to share with Jews "the hope of Jesus" should, therefore, first of all ask themselves a question about their real motives. Why do they want to "convert" Jews? Do they intend to transform them into their image and thus erase their Jewish identity?
So, to your difficult question, I will simply answer: Yes, it is possible for Christians to share this hope with the Jews. But, as you say, it must be done without threatening their Jewish identity. The richness and the beauty of their Jewish heritage should be respected.
The last line of this paragraph is profound.
This question may shock some Christians who hardly see any other values and truths outside of their own set of values and habits of thinking. This question is important, however, for it is a way of testing whether or not we have the right approach. Through that question, the Christian is compelled to resituate himself/herself, to test his/her convictions to make sure that his/her Christian faith is not a mere veneer of culture; that it is, indeed, a rich, vital, and profound experience that has a universal quality. In other words, the conversion of the Christian is a prerequisite for the conversion of the Jew.