Though we generally associate Yom Kippur with atonement, the Torah defines taharah (purification) as the day’s goal:

(כי ביום הזה יכפר עליכם לטהר אתכם מכל חטאתכם לפני ה' תטהרו (ויקרא טז:ל

On Yom Kippur, Hashem atones for our sins in order to purify us. 

The purification relates to both the Beit HaMikdash and the Jewish People.^[1] This is why the Yom Kippur Torah readings detail the purification of both the Beit Mikdash (in the morning reading^[2]) and the Jewish people (in the afternoon reading).^[3]

The Damage of Sin

We are familiar with how the concept of taharah applies to the context of ritual purity. We are not as familiar with its relevance to the non-ritual sense. What does taharah mean in a personal, spiritual context?

Understanding spiritual purity hinges on appreciating the impact that sin has upon us. Sin is not just wrong and damning; it also defiles our soul and spirit. Mitzvah fulfillment sanctifies; transgression defiles. Rav Chaim Volozhin^[4] compared sin to the consumption of unhealthy food. Just as the latter damages us physically, the former taints us spiritually.^[5]   

The Goal

(לב טהור ברא לי אלוקים ורוח נכון חדש בקרבי (תהלים נא:יב

Dovid HaMelech links taharah to the heart and spirit. The Shaarei Teshuvah^[6] and Mesilat Yesharim^[7] explain that taharah hinges upon motivation — the why of what we do (beyond what we do). Tahor people are motivated by their wisdom and fear of Hashem, not their base desires.

Taharah’s focus on the heart helps us understand why the Rambam^[8] sees teshuvah as addressing not just sin but also improper character traits. Purification is not just about correcting action but mainly about personal improvement.

Our Role

The pesukim we have seen — about taharah in general (Tehillim) and Yom Kippur specifically (Vayikra 16) — describe Hashem purifying us. This explains our request in each of our Shabbat and Yom Tov prayers: וטהר לבנו לעבדך באמת.

We ask Hashem to purify our hearts so we can serve him in earnest.

Crucially, though, the conclusion of the Yom Kippur pasuk — the word “tit’haru” — adds that we must purify ourselves.^[9] The Kohen Gadol used this word at the height of the Yom Kippur atonement service to remind those in the Mikdash of their responsibility to purify themselves. His verbal response to those who prostrated themselves upon his utterance of Hashem’s (most) sacred name was “tit’haru.” He emphasized that his avodah alone was not enough. Each person needed to purify himself.

When we make the effort to purify ourselves, Hashem completes the process for us. Shaarei Teshuvah^[10] summarizes the process this way:

הזהירנו הכתוב שנטהר לפני ה' בתשובתנו והוא יכפר עלינו ביום הזה לטהר אותנו^[11]

“The Torah commands us to purify ourselves through teshuvah before Hashem so He can purify us through His atonement.”

How We Purify Ourselves

Most of us are familiar with the process and stages of teshuvah. But how do we purify ourselves? The mishnah at the end of Mesechet Yoma gives us direction by describing Hashem Himself as the proverbial mikvah in which we are meant to purify ourselves.^[12] Hashem is totally disconnected from all sin and defilement. By reconnecting with Him, we return to a natural state of purity. Like the Kohen Gadol, who immerses himself ten times on Yom Kippur and then enters the holy cloud (created by the ketoret) within the holiest part of Hashem’s sanctuary, we also “immerse ourselves” within our connection to Hashem.

After elaborating on this notion, the Maharal^[13] emphasizes that, like immersion in an actual mikvah, we only achieve taharah by connecting (through committing) ourselves fully to Hashem. Even a tiny chatzizah (separation) makes the “immersion” completely meaningless. 

Returning to Ourselves

On a more profound (yet simpler) level, our return to Hashem is a return to our natural, authentic selves.

This applies on two levels. Firstly, because our soul emanates from Hashem,^[14] we need to look no further than inside ourselves to find His holiness. As the Torah writes: “It is not in the sky or beyond the seas but in our mouths and hearts.^[15]

Secondly, because our soul is of godly origin, reconnecting with Hashem ultimately reconnects us to our true selves. For this reason, Rav Kook explained that our return to Hashem regenerates our natural, holy soul.^[16]

We find Hashem by looking inside ourselves and our true selves by reconnecting with Him.

Though taharah is always an important goal, Yom Kippur is when this self-purification is most possible and impactful. Let’s make sure to take full advantage of the opportunity.

[1] This explains the centrality of purity to Yom Kippur ritual, which can be seen in the need for tevilah (ten times by the Kohen Gadol and customarily performed by all males before Yom Kippur) and the custom to wear white.

[2] Vayikra Perek 16.

[3] Perek 18 describes sexual sins as defiling us in pesukim 20, 23, and 24. The next pesukim (25–30) describe how these sins defile the land as well. See also Bamidbar 35, which depicts murder as defiling the land.

[4] Nefesh Hachayim 2:8.

[5] In addition to the damage caused on the spiritual plane, the Gemara in Yoma (39a) depicts how sin damages even one’s intellectual capacity (see also Or HaChayim to Vayikra 11:43).

[6] 1:9.

[7] Perek 17 — Midat Hataharah.

[8] Teshuvah 7:3.

[9] See Shaarei Teshuvah (2:14, 4:17), who sees this phrase as the basis of the unique chiyuv to do teshuvah on Yom Kippur.

[10] Shaarei Teshuvah 2:14.

[11] The duality of Hashem purifying us and our self-purification is presented by the Mishnah 85b. See also Yoma 39b.

[12] See Rambam Mikvaot (11:12), who also uses immersion in a mikvah as a model for personal purification. 

Shaarei Teshuvah 4:17 also speaks of teshuvah as necessary for taharah. Obviously, purification is only possible once we have distanced ourselves from and atoned for our sins.

[13] Kitvei Maharal, D’rush L’Shabbat Shuvah.

[14] Bereishit 2:7 with Rashi and Ramban.

[15] Devarim 30:11-14.

[16] Orot Hateshuvah 15:10. The morning prayer of Elokai Neshama builds off this idea.