(13) If thou turn away thy foot because of the sabbath, From pursuing thy business on My holy day; And call the sabbath a delight, And the holy of the LORD honourable; And shalt honour it, not doing thy wonted ways, Nor pursuing thy business, nor speaking thereof;
The Sabbath (1951), Abraham Joshua Heschel
The meaning of the Sabbath is to celebrate time rather than space. Six days a week we live under the tyranny of things of space; on the Sabbath we try to become attuned to holiness in time. It is a day on which we are called upon to share in what is eternal in time, to turn from the results of creation to the mystery of creation; from the world of creation to the creation of the world.
"Thinking Shabbat" Rabbi Lawrence Kusher in A Shabbat Reader p 199-201
We need a way to describe liberal Jews who are serious about Shabbat. Shomer Shabbat, Keeper of Shabbat, based as it is on the language of the actual commandment in Deuteronomy, could be ideal. Unfortunately it has been appropriated and defined, meticulously and oppressively, by someone else. So we return to the text of the Fourth Commandment and realize that it is said twice, once in Deuteronomy and again in Exodus. In Deuteronomy (5:11) we are told "Shamor," keep the Sabbath. But in Exodus (2;7) the verb is different: we are told "Zachor," remember the Sabbath. Perhaps it is for us to create a new standard of Shabbat behavior called "Zachor Shabbat." One who is "Zocher Shabbat" would remember throughout the day's duration that it was Shabbat. (Not so easy as it first sounds.) We say to one another, Do anything you want--as long as you will remember that it is Shabbat, amd that will insure that whatever you do will be lichvod ha-Shabbat, for the honor of the Shabbat.