Parshat Nitzavim: Jewish living is a realistic and holistic practice

(11) Surely, this mitzvah which I command you this day is not too wondrous for you, nor is it far (12) It is not in the heavens, that you should say, “Who will go up for us to the heavens and take it for us and make us hear it, that we may do it?” (13) Neither is it beyond the sea, that you should say, “Who will cross to the other side of the sea and take it for us and make us hear it, that we may do it?” (14) The thing is very close to you, in your mouth and in your heart, to do it.

(2) Shimon the Righteous was from the remnants of the Great Assembly. He would often say: "On three things the world stands: on the Torah, on the Avodah and on Gemilut Chasadim."

“with your mouth and your heart to perform it.”

The Torah mentions three things here: the mouth, the heart, and the doing. All the commandments of the Torah are included in one of these three categories.

There are commandments which need to be fulfilled by use of the mouth; others can be fulfilled by means of the heart (I.e. the intellect) only; still others require “doing.” This is what may have prompted our sages in Avot 1:2 to state, “The world stands on three things: on Torah, on the Avodah (the work/the service), and on Gemilut Chasadim.”

When the sages said: “on the Torah,” they meant "with your mouth," and regarding the Avodah (the work/the service) they meant "in your heart," which is the service of the heart; when they said: “on Gemilut Chasadim,” they meant "to do it."

It is known that the commandments that depend on heart (I.e. intellect) are greater service to the Holy Bountiful One than commandments that depend on speech, thus the Rabbis said that this is the reason that when someone who is engaged in studying Torah [using their mouth to serve the Eternal] must interrupt their studies when it is time to perform a commandment requiring our heart, i.e. the reading of the first line of the Shema [which requires mental concentration]...

Commandments that depend on speech are ranked higher than the performance of commandments which involve doing, such as offering sacrifices. (Tanchuma Tzav 14) This is based on Leviticus 7:37, since it does not say, “This is the Torah: a burnt offering…”, but rather “This is the Torah of the burnt offering…” [i.e. that there are viable or even superior alternatives to the offering of sacrificial animals. Ed.]

This is the reason the word ובלבבך, “in your heart,” has been written in the middle of the three categories, to emphasize its centrality, the fact that it is the most important of the three. This is why performance, i.e. with the limbs and organs of the body, has been written only at the end of the verse.

And God Gave. Empty heads ask, “What did Moses do on the mount for forty days and forty nights?” They do not know that if Moses spent this number and double its double in years with God, he would barely know one part of a thousand of God’s work and ways and the secret of all the precepts which God commanded him. They think that deeds are most important. This is not so. What is important is heart together with deed.

Heart and tongue train a person [to observe the commandments]. We thus read, in thy mouth (I.e. commandments observed through acts of speech), and in thy heart, (I.e. one must understand what one is doing), that thou mayest do it (I.e. commandments observed through physical action) (Deut. 30:14). Our ancients said, “God desires the heart.”

Loving and cleaving to God with all of one’s soul is the basis of the commandments. This cannot be completely accomplished if a person does not know God’s ways and is not acquainted with God’s work in the upper and lower worlds. The prophet thus states, But let the one that glories glory in this: That they understand and know Me (Jer. 9:23). It will then become clear to a person that God exercises mercy, justice, and righteous, in the earth (Ibid.).

A person cannot know God if they do not know their own spirit, soul, and body. For of what use is a person’s wisdom to them if they does not know the makeup of their soul?

Now Moses, who prophesied in the wilderness for forty years and was party to many secrets which God revealed to him on Mount Sinai, said before his death, O Lord God, You have begun to show Your servant Your greatness (Deut. 3:24). Thus it was only then that Moses began to understand God’s greatness and that the God’s greatness was shown to him. This is truth, for God’s greatness is unsearchable (Ps. 145:3).