The mitzvot of the number seven share a common denominator: they release our sense of ownership.
Shmita after seven years: the land is not yours, “for the land is Mine.”
Shabbat after seven days: time is not in your possession.
Niddah for seven days: your wife is not your property.
A slave goes free after seven years: human beings are not your property — “they are My servants.”
The seven days of Sukkot: your home is not your fortress. Go out to a temporary dwelling.
The seven days of Passover: your food and your wealth are not in your hands — eat the bread of poverty.
And after that internalization, these mitzvot almost always have the eighth day:
On the eighth of Shmita, everyone gathers for Hakhel.
On Sunday we return to the six days of labor.
On the eighth day of Niddah the woman immerses, and marital closeness returns.
On Shemini Atzeret, after Sukkot, we return to the solid house.
On the eighth of Passover — Shavuot, the festival of bread and leavened food.
The eighth day, on which we return to life, to the possessions we thought we owned — but we return a little differently, with the understanding that it is our task to act, to create, to make use of time and to work the land. Yet out of the understanding that we are forming a partnership — not ownership and conquest.
