Shortly after their marriage, the Rebbe and his wife moved to Berlin, where the Rebbe enrolled in the University of Berlin and took courses in philosophy and mathematics.

When Hitler came to power in 1933, the Rebbe and Rebbetzin relocated to Paris, where the Rebbe continued with his studies, at the Sorbonne and at a Parisian engineering college, until 1938.

As he pursued academic knowledge at the leading universities of Europe, the Rebbe’s primary occupations lay elsewhere—in his consummate immersion in Torah study, and his work on behalf of Russian Jewry and other communal affairs in conjunction with his father-in-law. To this end, the Rebbe made repeated trips to his father-in-law in Riga and later Otwock (a suburb of Warsaw), and Rabbi Yosef Yitzchak would stop at his daughter and son-in-law’s home in his travels through Europe.

Throughout the years of his leadership, the Rebbe addressed the faith/science nexus on a variety of levels. On the question of perceived contradictions between the two, the Rebbe rejected the “apologetic” approach which reinterpreted biblical passages and other articles of faith to better fit the prevalent scientific theory. There was a time, wrote the Rebbe in his numerous letters on the topic, when scientists believed that certain “facts” could be “proven” by the scientific method. Today, however, it is universally acknowledged that the scientific method does not “prove facts,” but rather assigns greater or lesser probability to a hypothesis. The believing Jew, who holds in hand a document which he knows to be the revealed word of the Creator of nature and its laws, has no reason—indeed, no scientific reason—to modify that truth because it seems to contradict a hypothesis to which science, in its present stage of development and drawing on its present reservoir of knowledge, has assigned a certain degree of probability.

The Rebbe's passport
The Rebbe's passport

But the Rebbe saw the faith/science relationship as collaborative in essence, rather than combative. On the most basic level, he saw endless opportunities for harnessing the technological fruits of scientific advancement to further the aim of the believer to make the world a better, more harmonious and more G‑dly place. On a deeper level, he demonstrated how certain truths about G‑d and His relationship with our reality have become more apprehensible to the human mind through the perspective on reality which modern science has opened up for modern man.

(One of many examples cited by the Rebbe: Integral to Jewish faith is the concept of “specific divine providence”—that G‑d is aware of and concerned with every event in the universe, from the birth of a star in a distant galaxy to the turn of a leaf in the wind in a remote forest, and that they all figure in His master plan of creation and contribute to its realization. In earlier generations, this idea lay beyond the realm of rational credulity. The believer could accept it only on faith. Today, when we can watch a spacecraft landing on Mars and use a chip of silicon to compute millions of data points a second, it requires no great “leap of faith” to understand that He who imparted such potential to His creation certainly possesses it Himself.)

Finally, the Rebbe saw science as a way to experience the divine: by delving into the nature of creation, we come to know, love and stand in awe before the face of its Creator. While this has always been the case, recent discoveries and theories in many fields of science have been leaping far higher in their quest for the “greater picture,” and penetrating far deeper to the essence of things, than ever before.

The Rebbe on Torah's Relevance

"The belief in a One G‑d leads to a belief in a one Torah, which compels that we should be 'a one people on earth.' In other words, in all matters a person should seek unity, for only then is the belief in the unity of G‑d complete."

"What is truly remarkable is that this idea has also gained prominence in the sciences, particularly in recent years. Increasingly, scientific theory and research is focusing on the endeavor to express all physical phenomena in a single formula and, more importantly, to discover the single unifying force which underlies all other forces, so that all other forces are shown to be aspects and outgrowths of this singular force."

From a letter by the Rebbe, March 1954 (free translation)