Likutei Moharan 22:9/ליקוטי מוהר"ן כ״ב:ט׳

19. Now, holy boldness is achieved through joy, as in (Nechemiah 8:10), “For the delight in God is your boldness.” In other words, [it is achieved] through the concept of “naaseh v’nishma (we will do and we will hear)” (Exodus 24:7). This is the concept of joy. As our Sages said (Shabbat 88a): “At the time that the Jewish people said, ‘We will do and we will hear,’ 600,000 angels descended and placed two crowns on the head of each one of them… and when they sinned, they were taken away. But in the Future the Holy One will return them [the crowns] to them, as is written (Isaiah 35:10), ‘an everlasting joy on their heads.’” Thus, “we will do” and “we will hear” are synonymous with joy, corresponding to “an everlasting joy on their heads.”

2And know! these two ornaments with which they were crowned at Chorev as a result of “we will do and we will hear” correspond to “In the beginning, He created.” As is brought in the fifth chapter of Sifra De’Tzniuta: “‘In the beginning’—this is a complete-statement; ‘He created’—a half-statement. This is Upper Eden, <and this is> Lower Eden; upper wisdom <and> lower wisdom; father and son.”

3For “we will do and we will hear” corresponds to [concepts] hidden and revealed. “We will do” is synonymous with the revealed—i.e., the precepts that each and every person can fulfill commensurate with his level. And “we will hear” is synonymous with the hidden—that which is elevated and hidden from him, so that he is incapable of serving [God] with this.

4For example: Every precept has that which accompanies it. Aside from the command recorded in the Torah to fulfill the precept, there are additional statements in the Torah, such as, “And God spoke to Moshe,” as well as the other statements of the Torah surrounding the precept.

5Now, the service which is contained in these Torah statements accompanying the precept corresponds to “we will hear,” the hidden. For the precept itself, <which we> can fulfill, <is called “we will do”>. But the service contained in these statements, we have no knowledge of—corresponding to “we will hear,” the hidden.

6This corresponds to Torah and prayer. “We will do” is synonymous with Torah—the revealed, that which we know to fulfill. “And we will hear” is synonymous with the hidden, corresponding to the statements of Torah. These are the statements of Torah accompanying each precept—the concept of hidden, with which one does not know how to serve the Holy One. It corresponds to prayer, <which itself indicates> a cleaving [to God]. This is because “hearing is dependent upon the heart” (Tikkuney Zohar #58), as is written (1 Kings 3:9), “Give Your servant a hearing heart.”

7And the service of the heart is prayer (Taanit 2a) —namely, negation [of the self] and cleaving to the Infinite One. This is because, conceptually, the Infinite One is that of which we have no grasp. And, because one has no grasp of this {namely, of the above mentioned statements of the Torah, for it is the concept of hidden}, it corresponds to prayer/cleaving to God—which is nothing other than negation [of the self] to the Infinite One.