The Hebrew word for repentance, teshuva, also means returning. God is the source of all creation, and when a person repents, he returns to the source of his creation. When one who distanced himself from God through sin then returns to Him out of love, he transforms a negative into a positive. Distancing himself from God, which was at first tragically negative, is ultimately a positive, because it brought him closer to God.

Repentance is when a person returns to God with all of his heart and soul. This is part of the world order, for this world returns to God. The world has no independent existence, and returns to God from where it came and where all in existence return to. This is what keeps them in existence, for they return to God… Because repentance is the return of elements of creation to God just as they came from Him, when a sinner returns to God, even his willful sins become as merits, for here there is a returning to God and a return to the proper order of the world. Therefore, when this sinner repents – he who distanced himself from God through his sin, and the distance necessitated returning to God, his distance becomes a merit, for there is now returning to God. This is the case only when the repentance was out of love, for love involves totally clinging to God. (Maharal, Netivot Olam, Netiv HaTeshuva 2)

Man’s soul is holy and connected to God, but sins conceal its light. When a person repents, his soul once again shines within him, as well as in its spiritual source above.

Every Jewish person has a point that is holy to God, and it is the living soul. It is through sins that the burden of materialism and physicality conceal the light of the soul and it cannot illuminate…. To the degree that he returns the power of his soul into his body, so will the power of his soul illuminate its spiritual source above. (Rabbi Yehuda Aryeh Leib Alter, Sefat Emet, Nitzavim 5635)

Repentance is the return of the soul to its place. The mystics distinguished between higher and lower repentance. Lower repentance is repenting for improper acts and the soul returning to its source after having been distanced through sin. Higher repentance is when the soul clings to and comes close to the Creator, exactly as it was before it descended into a body.

Lower repentance:

So it is written: “Jacob the allotment [ĥevel] of His inheritance” (Deuteronomy 32:9). By analogy, [the soul is] like a cord with one end above and the other end below. If a person pulls the lower end, he will dislocate the higher end and pull it toward him as much as it is possible for it to be pulled.

It is literally the same with regard to the root of the human soul.… He pulls down its sustenance through his evil deeds and thoughts into the sanctums of the “other side,” so to speak, from which he receives his sinful thoughts and deeds…. When a person repents properly, he then extracts from them the sustenance, which he channeled through his actions and thoughts.

For through his repentance, he restores the sustenance of the Divine Presence to its place.

Higher repentance:

Once the wind has passed and cleansed them, then their soul is able to return literally to Being, blessed be He, and ascend upon high to its source and cling to Him in wondrous union… This constitutes complete repentance. The aspect of this unification and repentance constitutes the aspect of higher repentance which follows lower repentance. (Rabbi Shneur Zalman of Liadi, Tanya, Igeret HaTeshuva, 6–8)