Shame and Brazenness
2. One must habituate himself to speak between himself and his Creator with great sincerity until he begins to speak words of truth [that are] in his heart, with the heat that is in the heart, in an arousal of repentance. [He should do this] until he sees his [own] insignificance and [sees] the greatness of the Creator, until he becomes very ashamed before HaShem. For until now, he threw his sins over his shoulder and didn't look at them; and now that he knows them, great shame then enters him over the greatness of his transgressions against the Mighty One, the Ruler, the essence and source of all the worlds.
And at the beginning, the shame is not yet in actuality before his face because his sins have stupefied his mind and awareness via the spirit of folly within him. Therefore, before he merits complete repentance, he doesn't have much divine knowledge to become ashamed properly, to be ashamed according to the vastness of his transgressions and according to the greatness of the Creator whom he sinned against. However, afterwards, when he repents and removes the foolishness from him and adds intellect in himself, then he will become exceedingly ashamed and the shame will be revealed on his face. This shame is the aspect of the light of the tefillin which are the sign of clinging to the Creator, the aspect of beaming light of the face, and through this shame all his transgressions are forgiven and he clings himself to the Tree of Life. (From Likutei Moharan I, 38; see sec. Speech 7)
3. One who brazenness of the forces of evil and doesn't become ashamed from the true tzadikim nor the [God-]fearers nor the [truly] good men - it is definite that his feet of his fathers did not stand at Mt. Sinai, and he damages the holiness of tefillin, which correspond to the Tree of Life, and he clings himself to the Tree of Death and [thus] he is banished from the Garden of Eden and he descends into Geihinnom. When he repents and is ashamed about his transgressions, through that he is immediately forgiven and he returns to himself divine knowledge and mind and he divorces the spirit of folly from his midst; he merits the aspect of the light of tefillin which corresponds to the beaming light of the face, the aspect of the Tree of Life. (There^)
4. The main repentance is through shame because a person must be very, very ashamed of himself. For a transgression is definitely shame, God forbid, because a transgression doesn't belong to and isn't appropriate to Israel at all. For the Israelite man is far from the source of transgression completely, and definitely it isn't attractive to the Israelite man to have transgressions, God forbid. However, also when he wants to do a commandment, it is proper that he should have great shame - because what merit does he have that he should merit to do the commandment? And how could be brazen his face to enter into the chamber of the King to do a commandment? He should weigh in his mind before who he is doing the commandment, and [he should also weigh] the degree of the commandment because the vastness of preciousness of the level of the commandment itself has no measure.
It is definitely proper that great shame should fall on him when he comes to do some commandment. How [can he] come to snatch tefillin, which are the crowns of the King, and place them on his head all the sudden? It is definitely proper that great feel should fall upon him. If a person had shame, he would be ashamed before HaShem even to take food into his mouth, for what merit does he have that he should have food? Yet, the main part of shame is merited through seeing oneself with the true tzadik, and through that repentance is merited, for repentance is essentially through shame. Through it, true humility is merited, which corresponds to the humility of Moses our teacher, which is the essence of life; [that is,] the aspect of eternal life of the world to come. (From Likutei Moharan II, 72)