“Come to me, all of you who are weary and carry heavy burdens, and I will give you rest. Take my yoke upon you. Let me teach you, because I am humble and gentle at heart, and you will find rest for your souls. For my yoke is easy to bear, and the burden I give you is light.” (Matthew 11:28-30)
The word "Sabbath" means to "stop." Stop working. Stop striving. Stop worrying. Stop accumulating. Just stop. It's a concept bound up in the fabric of creation itself. On the 7th day of creation, God stopped his work in order to rest and enjoy the fruit of his labour (Genesis 2:1-3).
The Sabbath was also "blessed" by God. His blessing of the Sabbath indicates that this perdiod of rest is actually productive even when we are not. God's blessing comes with fruitfulness and multiplication. Something about practicing Sabbath actually creates more even when we are doing less.
Sabbath, then, is the practice of taking a regular (weekly) 24 hour period to stop. No work. No pursuing. No striving. No "have-to's." It's a day to enjoy the fruit of our work, worship our creator, and bask in his provision. It's a day to be thankful for what we have rather than striving for more. Moreso, it's a day to enjoy our God-given freedom from the slavery of production:
“To refuse Sabbath is in effect to spurn the gift of freedom. It is to resume willingly what we once cried out for God to deliver us from” ~Mark Buchanan