This week's Parsha was written by Rabbi Rachel Barenblat a poet and chaplain an who blogs as the Velveteen Rabbi.

This week's Torah portion, Ki Tisa, begins with Moshe/Moses atop Mount Sinai, communing with God. The last thing God says to Moshe is a set of verses we now know as V'shamru [Exodus 31:16-17], commanding us to keep Shabbat throughout the ages as a sign of covenant with God.
Then God gives Moshe the two tablets, inscribed by God's own hand.


טז  וְשָׁמְרוּ בְנֵי-יִשְׂרָאֵל, אֶת-הַשַּׁבָּת, לַעֲשׂוֹת אֶת-הַשַּׁבָּת לְדֹרֹתָם, בְּרִית עוֹלָם.

יז  בֵּינִי, וּבֵין בְּנֵי יִשְׂרָאֵל--אוֹת הִוא, לְעֹלָם:  כִּי-שֵׁשֶׁת יָמִים, עָשָׂה יְהוָה אֶת-הַשָּׁמַיִם וְאֶת-הָאָרֶץ, וּבַיּוֹם הַשְּׁבִיעִי, שָׁבַת וַיִּנָּפַשׁ.

Exodus 31

16 Wherefore the children of Israel shall keep the sabbath, to observe the sabbath throughout their generations, for a perpetual covenant.

17 It is a sign between Me and the children of Israel for ever; for in six days the LORD made heaven and earth, and on the seventh day He ceased from work and rested.' 

Meanwhile, the people are anxious. Moshe has been gone for a long time. They implore Aaron, his brother, to "make them a god." They donate their gold jewelry, and from that jewelry a calf is fashioned, which they begin to worship.
When he comes down the mountain, Moshe shatters the tablets in fury.
Many commentators have seen this incident as a kind of spiritual "adultery." Here is God reminding us of the Shabbat which serves as the sign of our eternal relationship, and meanwhile we're off giving ourselves over to something that is not God. 
The Torah frequently compares our relationship with God to a marriage... and here we are, "cheating on" God when the ink on our ‘ketubah’ (marriage contract) is barely dry.
As punishment, Moshe grinds up the calf and makes the people drink it -- which is strikingly similar to the punishment for a woman accused of adultery, as described later in Torah.
I'm always struck by the symbolism of making the people confront their own misdeeds in this way. They have to literally swallow what they have done. They have to take ownership of the damage they have done to their relationship with God.
Seen in this light, Moshe's shattering of the tablets is a sign of the spiritual brokenness in that relationship.
But what becomes of those broken tablet stones?
We read in Talmud:

Rabbi Joshua ben Levi said to his sons: Have care for an old person who has forgotten his/her learning. For we say: Both the whole tablets and the shattered tablets lie in the Ark. (Talmud Bavli, Berakhot 8b).

In the ark of the covenant, which will be kept inside the mishkan / dwelling-place (or Tabernacle) for God, our ancestors carried both the second set of tablets (which are whole) and that first set of tablets (which are broken).
For Rabbi Joshua ben Levi, this holds a message about how to treat our elders. Just as we cherished both sets of tablets, so we should cherish both those who are whole, and those whose wholeness has been broken by sickness or by age.
Perhaps when Moshe broke the tablets, he was demonstrating his own brokenness. His wholeness was broken when his people demonstrated their lack of commitment and faith. 
Just as our ancestors kept the broken tablets along with the whole ones, we cherish the memory not only of Moshe's beautiful moments, but also his times of imperfection and anger.
Each of us is like Moshe. Each of us carries her own history in the ark of her own heart.
In our own holy of holies, we hold our sweetest memories -- and also the times when we have felt shattered. Without both, we wouldn't be who we are.
How does all of this relate to Shabbat and to V'shamru?
The verses of V'shamru, from this week's portion, charge us with keeping Shabbat as an eternal covenant. It is a sign, God says, between us for all time. A reminder that on the seventh day God rested and so do we.
Shabbat is a covenant between us and God. 
When we keep Shabbat -- whatever that means to us; as liberal Jews we shape our Shabbat observance in accordance with a variety of values -- but when we keep Shabbat, however we keep Shabbat, we re-enact the covenant.
Every week, we renew our wedding vows with the Holy One. We reprise the central act of our relationship, an act of pausing to notice the sacredness of creation.
Every Shabbat is the antidote to the sin of the Golden Calf. Then we were anxious, and we put our faith in something gleaming, something we could see and touch.
Now we remind ourselves that relationship exists even when we can't see it. That when we make Shabbat, we emulate the ineffable force behind the cosmos in rhythms of creation and rest.

Shabbat Shalom