Charles Bradford notes in his book Sabbath Roots: The African Connection that:
Sabbath is a promise of heavenly rest, a gift that brings with it a token or pledge of life in the escheton, the kingdom of God. It is God’s future experienced in the now. A portion of eternity set in the midst of time.
The Sabbath is promise, but it is experienced now. The Sabbath is the Kingdom of God experienced and brought to today. The Sabbath is our ability to catch a glimpse of what the future Kingdom will be about. The Sabbath is our proof that the future Kingdom will come to past. We are certainly called to talk about and preach that Sabbath.
Here is an interesting quote from Heschel’s book the Sabbath.
Judaism teaches us to be attached to holiness in time, to be attached to sacred events, to learn how to consecrate sanctuaries that emerge from the magnificient stream of a year. The Sabbaths are our great cathedrals; and our Holy of Holies is a shrine that neither the Romans nor the Germans were able to burn; a shrine that even apostasy cannot easily obliterate
“When history began, there was only one holiness in the world, holiness in time.”
When God gave us the Sabbath, God gave us something that could not be taken away by others. The Sabbath is something that we can only take away from ourselves.