Selichot, the ceremonial and first formal prayers of repentance mark the unofficial start of the "High Holiday" experience, in practice, for many. In the Ashkenazic rite, there must be at least three days of selichot recited before Rosh Hashana, but they also must begin on a Saturday night. And so they start either the Saturday night before Rosh Hashana when it falls late enough in the week, or, as is the case this year, more than a week in advance. But why must they start on Saturday night?
In his Orot HaTeshuva (Lights of Penitence), Rav Kook zt''l begins by speaking of physical teshuva (penitence):
The science of medicine concerns itself a good deal with this, but this important phenomenon has not yet been fully clarified. We have not yet found the answer to all questions pertaining to physical penitence, to clarify how far it is possible within the delimitations of existence to restore to a person all the losses sustained as a result of those offenses that damage the body and its functions. It appears that this phase of penitence is linked in a profound way with other forms of penitence - the spiritual phase of natural penitence, and penitence according to faith and penitence according to reason.
Rav Kook is focused very much on the notion that moral failings will manifest physically. And that is true. And in touching on the subject, he highlights that the state of the physical body is "linked in a profound way" with everything else. And since the link is profound and accessible from both sides, teshuva can happen by examining our actions and spiritual state, yes, but it can also happen physically and affect our spiritual state and actions. Don't believe it? Ask anyone who's ever been stressed, and therefore curt with a loved one or friend, or quick to anger, or whatever the example might be, and then went for a good run, and was suddenly merciful, compassionate, and slow to anger all over again. In context, doctors are agents of teshuva, as are personal trainers, yoga instructors, and scenic walks like Blackstone Blvd.
The first of the three priestly blessings is, "May the Lord bless you and protect you." Without safety and security, subsequent spiritual blessings of enlightenment and peace are unthinkable. Acute awareness of the limitation of resources, pressing conflict, physical and emotional danger prompt activation of a survival-mode adrenaline fueled way of being that, while necessary at times, is counterproductive and destructive at others. In that place, we will need to be right, to feel superior, to compare and be better.
And so return, course-correction, soft but honest self-evaluation is more likely after a day of plentiful food, song, physical rest, a nap, and perhaps an afternoon stroll. Enlightenment comes only after blessing and security. The poem from the selichot says, "במוצאי מנוחה קדמנוך תחילה". It might well be translated as, "At the close of rest, we approach you immediately." Alternatively, it could be translated as, "At the close of rest we first approach you." Reflection only after peaceful rest.