Come and eavesdrop on a question I was asked by a leading Anglican bishop at an interfaith symposium last summer. "Rabbi," he asked earnestly, "how can your people turn Gaza into a concentration camp after Auschwitz?" This being my first encounter with this type of dovetailing - as employed last week by Respect's Lee Jasper and this week by Liberal Democrat David Ward - my reply was forgettable. Lately, my responses are improving.
When Jews and Christians discuss the Holy Land it is this that fundamentally bothers many of my Christian colleagues: How could the victims of the last century's worst atrocity -they ask, faces pained - have begun to act so atrociously?
Church leaders are not the first to castigate Jews as poor students of their own history. Portuguese Nobel laureate José Saramago announced in 2002 that the blockade of Ramallah was "in the spirit of Auschwitz". In Brazil, a few months later, Saramago announced that the Jews no longer deserved any "sympathy for the suffering they went through during the Holocaust… They didn't learn anything from the suffering of their parents and grandparents."
Dr Haider Eid, professor at Al-Aqsa University sang a similar if slightly shriller tune in a 2010 speech to the University of London. "It is that the world was absolutely wrong to think that Nazism was defeated in 1945," he observed. "Nazism has won because it has finally managed to Nazify the consciousness of its own victims."
But what is striking in my conversations with Church figures is how pervasively the association between Israelis and Nazis has slipped into common parlance. At the Methodist Conference in June, a delegate cautioned me to prevent a "second Shoah upon the indigenous Palestinian people". I was asked by a sincere Quaker if the "settlers ever visited Yad Vashem". In a letter to the Church Times last year, John Pearson, chair of the Christian Sea of Faith Network, justified a pro-Palestinian event in Newcastle by remarking that the images of West Bank Palestinians waiting to enter Israel "reminded me strongly of similar photos of 70 years ago, showing vast armies of the innocent being herded into captivity". He failed to acknowledge that these Palestinians were not being herded into anything worse than a long day's work.
There are two salient questions, I think, that emerge from this new language of parallelism between Auschwitz and Gaza. The first is that the Jewish community must be extraordinarily cautious in how we justify Israel through the Holocaust. The line of reasoning that runs from the Holocaust to the state of Israel, is - in misguided hands - a two-way street that also links Israeli soldiers to Nazi stormtroopers.
The second is that European Christendom may have unfinished business with the Holocaust. Once we acknowledge the heroism of Martin Niemöller or the brave establishment of the Council of Christians and Jews, there are vanishingly few instances of Christian leaders saying a definitive "nein" against Nazism. I am neither a Christian nor an historian, but Christianity might engage in hard soul-searching on the silence that echoes out from that dark night.
Unfortunately, there is a linguistic trick that washes the stain of the Shoah from the Christian record. What if the victims of the Holocaust, when eventually given power over another people, acted just like Nazis? If the Jews can build concentration camps in Gaza, then the Christians who simply watched them being built in Poland cannot be judged too harshly.
With the linguistic trick, Christian guilt vanishes. The German pastors who prayed on Good Friday for the "Perfidious Jews" while the ovens smoked are as equally culpable - and thus, as equally blameless - as those settler rabbis who remain silent against the racial injustices in Hebron within sight of their own homes. Do these dark symmetries between Auschwitz and Gaza clear Christianity of its own Holocaust silence, just as Pontius Pilate once washed his own hands to place the blame on Jewish heads?
The Middle East is in desperate need of non-biased voices and agenda-less honest brokers. What it certainly does not need is more entangled histories, more unnamed ghosts of past horror. We Jews and Christians must speak together about the future of Israel and Palestine, but first we must speak together about our own shared and freighted past.