A good excerpt, on the subject of Sabbath, from the book Leadership from the Inside Out by Kevin Harney. (Written to pastors, but good application for all)...

"Each time we take a Sabbath, we make three declarations to heaven, earth, our church, and ourselves.

1. We trust that God is capable of running the universe and his church without us.

2. We are confident that God can provide all we need in six days of labor.

3. We understand that slowing down and meeting with God and his people is a priority in our lives.

As leaders, we can't call people to experience the joy and strength of rest if we aren't modeling this practice. Leaders who refuse to take a full day off each week make a profound theological statement: I am more powerful and important than God. Does that sound overstated? Think about it. God, who is omnipresent, took a Sabbath and called you to do the same. You, who are limited, refuse to take a Sabbath day. What message are you declaring by this behavior?"