Yes, I would say Shabbat is, or could become, a day of spiritual cleansing. Seriously observant Jews actually prepare for the Sabbath on Friday afternoons by going to the mikvah, or ritual bath. The details of the mikvah are not relevant here, but suffice it to say this is a powerful act of physical cleansing and spiritual renewal. If we were to promote the Sabbath as a spiritual cleansing of sorts, I suggest we promote going to the mikvah to begin the spiritual cleansing with a physical cleansing as well.
Early Judaism was a very body-affirming faith. The fact that God looks upon the physical world and proclaims it “good” makes it clear that the physical and material are not the enemies of the spiritual. I worry that a kind of Gnosticism has crept into our spirituality. We have separated body and spirit, and denigrated the former while elevating the latter. I don’t see the separation as valid.
If, as I believe, God is the Source and Substance of all reality God’s body is the universe itself and everything in it, from quarks to quasars. My body is part of the Divine Body, and should be honored as such. To think we can only get to the spirit by negating the body is to insist on a dichotomy that God would not recognize.
Having washed away the grime that covers the body, we are then ready to wash away the grim that covers the spiritual body. We have already spoken of the Sabbath as play, and I suspect that when we cleanse ourselves of the illusions and delusions that pass for spiritual knowledge and wisdom we will discover the playful te (way) of God. Religion has become a grim business for many of us. So rooted in fear, we have stripped religion of joy, and made it all so deadly and dreadfully serious.
I agree as well that the process of freeing ourselves from the false is, as you have said, a kind of death. This is what the Sufi’s call “dying before you die.” It is a psychological death; a dying to the false and a rebirthing into the true which returns us to God as the power that liberates us from the narrow places of our egos’ creation.
As to your thought that none of this can be done by the ego itself, I would again happily agree. The ego cannot surrender itself to God, for the very thing that needs to be surrendered is the thing doing the surrendering. The ego must be surrendered by something greater than it, i.e. Ruach HaKodesh, the Holy Spirit.
So much of contemporary spirituality is simply the subtle machinations of the ego. The ego pretends to surrender as a means of maintaining control. True surrender happens only when the ego is pushed to the limit. This is what Twelve Step people call Hitting Rock Bottom, and what others might call The Dark Night of the Soul. Whatever we call it, it is only when the ego realizes it cannot save itself that it is surrendered to a Higher Power that can bring about the salvation that is dying to the false and rebirthing to the true.
Sabbath Keepers might form communities, just as Twelve Steppers have their meetings, so I am not opposed to organization per se. I just worry that the organization eventually take precedence over the practice and the message, at which point that the whole thing is doomed.