To love the Lord your G‑d and to serve Him with all your heart (11:13)

What is the service of the heart? This is prayer.

- The Talmud, Taanis 2a

When Rabbi Schneur Zalman of Liadi neared his twentieth year, he decided - with the consent of his wife, Rebbetzin Sterna - to travel to a center of Torah learning and service of G‑d.

At that time, circa 1764, Vilna and Mezeritch were the great Jewish capitals of Eastern Europe. Vilna was the seat of Rabbi Eliyahu, the famed Gaon of Vilna, and Mezeritch was the hometown of Rabbi DovBer (the 'Maggid'), leader of the chassidic movement.

Related Rabbi Schneur Zalman: "I debated as to where I should go. I knew that in Vilna one was taught how to study, and that in Mezeritch one could learn how to pray. To study I was somewhat able, but of prayer I knew very little. So I went to Mezeritch.

"The Almighty blessed me with making the right choice. I became a devoted chassid of the Rebbe's and, upon my return to Vitebsk, I guided my disciples in the teachings of chassidism, which were well received by them."