Behind the Iron Curtain, there are Jews who are in an extremely precarious position, to the extent that they must have self-sacrifice for every aspect of fulfillment of Judaism. Nevertheless, they do not worry about their physical wants… There are Jews who do not have tefillin! When a Jew manages to procure tefillin, he cannot go to the synagogue to put them on, for if they catch him he will lose his employment... He lives in a joint house and has no choice but to put on the tefillin in a corner of his room such that his neighbor will not see him... Despite all this, such Jews make no calculations regarding what the next day may bring; their whole desire is to be able to put on tefillin...

From a tear-choked address by the Rebbe, April 17, 1982