The Rebbe’s father explains that the spiritual service represented by the Jewish slave is the journey from “immature intellect,” a Divine service motivated by an emotional appreciation of G-d, to a deeper, mature intellectual appreciation of the Divine Reality. The severance gift given at the end of the service is this gift of “mature intellect.” Freedom in kabbalah is associated with intellect, and so the fact that the severance gift is itself the gift of freedom aligns nicely with the legal definition of the severance gift, that it is the completion of the former slave’s freedom.
Based on this we can also explain the reason why severance gifts are only given to Jewish slaves and maidservants, but not to Cannaniate slaves who are occasionally redeemed for the purpose of a mitzvah. The Jewish slave alludes to the spiritual service of an emotional attachment to G-d. When this service is complete, the person graduates to an intellectual appreciation of G-d. But the Cannaniate slave alludes to the spiritual service of submission to G-d which never wavers or changes. For this service, there is no end, and no “freedom” or graduation to intellect, because intellectual appreciation would only interfere with the simple submission of the slave.
Nonetheless, the mainstream service of the Jewish people is that of the Jewish slave, not the Cannaniate slave’s submission, for the ideal form of divine service is one that involves the selfhood, emotions, and intellect of the person.
