The Sabbath A Great Cathedral

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

And

"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.