The Torah reading of Ha’azinu opens with Moshe’s words: “Listen heaven and I will speak; hear earth the words of my mouth.”1 With these words Moshe called upon heaven and earth to bear witness concerning his admonitions and exhortations in the “Song of Ha’azinu ” regarding the Jews’ performance of Torah and mitzvos.2

Sifri3 offers the following reasons for Moshe’s selection of heaven and earth as witnesses:

a) “ ‘Listen heaven’ — because Torah was given from heaven; ‘hear earth’ — because upon it the Jewish people stood when they [accepted the Torah and] said ‘All that G‑d spoke we shall obey and hear.’ ”

b) “ ‘Listen heaven’ — they did not perform those commandments that are bound up with [the astronomical calculations of] “heaven,” namely, adding a leap month and establishing the beginning of new months; ‘hear earth’ — they did not perform those commandments that are bound up with earth, namely, Gleanings, Forgotten Sheaves….”

c) “ ‘Listen heaven’ — they did not perform any of the commandments that are bound up with “heaven”; ‘hear earth’ — they did not perform any of the commandments that are bound up with the earth.”

Torah and mitzvos were, of course, given by G‑d, who is infinitely higher than either heaven or earth. In seeking to encourage a more perfect obedience to G‑d’s will, it seems logical to stress that Torah and mitzvos were given by Him, rather than focusing on the fact that they are connected to heaven and earth. Why the emphasis on heaven and earth?

A Jew is expected to serve G‑d in two opposite ways: on one hand he is expected to serve with pure and simple faith and with acceptance of the Heavenly Yoke — elements that derive from the soul’s essence. On the other hand, his service must permeate his intellect and emotions so that they too understand and experience G‑dliness.

In practical terms, this means that a Jew is to draw down and connect his soul’s essence with his inner powers, so that not only does he serve G‑d in thought, word and deed out of simple faith, but he also comprehends G‑dliness in his mind and loves and fears Him in his heart.

Moreover, a Jew is expected not only to serve G‑d in the general and ongoing manner of regular Torah and mitzvos , but also through repentance, teshuvah. This level of service — a level that emanates from the soul’s essence and seeks the innermost aspect of G‑dliness — must permeate a person’s intellect and emotion as well.

This is why when Moshe desired to rouse the Jews to the service of Torah and mitzvos , the performance of which was to reflect not only pure faith but the inner powers of intellect and emotion, he mentioned that Torah and mitzvos were given through heaven and earth.

He did this in order to arouse within Jews their level of heaven and earth, i.e., their loftier inner powers of intellect and thought which are likened to heaven,4 and the lesser powers of emotions, speech and action which are likened to earth.

These three levels — the soul’s essence, the soul’s “heaven,” and the soul’s “earth” — find general expression in the three manners of teshuvah : (1) an expression of the soul’s essence, (2) the service of Torah study — an expression of the soul’s intellect, and (3) the performance of mitzvos — an expression of the soul’s “earthy” aspect.

It is to these forms of service that the Sifri alludes in its three commentaries. The first comment of the Sifri speaks of service the mainstay of which is intellect and “heaven.” The second comment speaks of the performance of mitzvos concerning which we say that “action is what is most important” — the level of “earth.” The third comment speaks of teshuvah , for which reason Sifri states: “they did not perform any of the commandments” — a sorry state of affairs that necessitates teshuvah , which emanates from the soul’s very essence.

Based on Likkutei Sichos Vol. IV, pp. 1154-1158.