Where did the Rebbe learn this Christian view on the age of the universe?
At the University of Berlin in a Natural Philosophy class. For the past forty years, the Rebbe’s followers have been pushing this un-Jewish view, preaching it on college campuses and publishing it in newsletters, newspapers and on the internet. But, if the Slifkin Ban has taught us anything, it is that ignorance – both of science and of Jewish history – is not unique to Chabad. You can read the entire letter here.