Our Gemara on Amud Aleph quotes a verse in Vayikra (16:34) that refers to the sacrificial rites of Yom Kippur as “once a year.” We also have a similar verse in Shemos (30:10), which actually mentions that the Yom Kippur service is “once a year” two additional times in that verse. It is fair to say that most every holiday happens only “once a year,” so what is the Torah expressing when it emphasizes this annual aspect of Yom Kippur?

Sefas Emes (Acharei Mos 19) offers a beautiful idea. Yom Kippur is the only time that a mortal is allowed in the Holy of Holies, perhaps the greatest concentration of divine presence in the world. He says this is no coincidence. It is precisely at the time when atonement and forgiveness are sought and achieved that the greatest closeness to God is accomplished. This is because, ironically, new heights can be achieved after a restoration and repair that is even beyond the original state prior to the sin. As our sages say (Berachos 34b):

In the place where penitents stand, even the full-fledged righteous do not stand.

As we have remarked many times in our studies of psychology and the daf, there are recurring patterns throughout the physical, spiritual, and emotional worlds. This is another example of that, whereby we naturally see, whether it is recovering from an illness and thereby developing a stronger immunity, repairing a relationship and achieving new levels of understanding and intimacy, or coming to a place of repentance and return to God. In all of these situations, there is deep truth that the sin and rupture itself contributes to an ultimate realization and recovery, when properly handled, that becomes greater than the original situation.

One final point in regard to this. The Chofetz Chaim (Shemiras Halashon II:5) also notes the uniqueness of the Yom Kippur rites. The once-a-year entrance into the Holy of Holies must be preceded by the incense offering (see Vayikra 16:2), which is classically seen as atonement for l’shon hara (Yoma 44a). He says this shows that a prerequisite for meeting God in the Holy of Holies is not merely generic atonement, but of all things, a priority is placed on atonement for l’shon hara. The message is clear that we cannot achieve connection to God until we have properly repaired our connections with others.