|What's the point of Sabbath?|
The first is Exodus 20: 8-11: "Remember the sabbath day, and keep it holy. For six days you shall labor and do all your work. But the seventh day is a sabbath to the Lord your God; you shall not do any work—you, your son or your daughter, your male or female slave, your livestock, or the alien resident in your towns. For in six days the Lord made heaven and earth, the sea, and all that is in them, but rested the seventh day; therefore the Lord blessed the sabbath day and consecrated it."
The second is John 5: 17-18: "But Jesus said, “My Father has never stopped working, and this is why I keep on working.” Now the leaders wanted to kill Jesus for two reasons. First, he had broken the law of the Sabbath. But even worse, he had said God was his Father, which made him equal with God." CEV
In Matthew 12 and Mark 2 the question is not about the importance of the sabbath, but, what kind of behavior is lawful. More importantly, who decides what is lawful or not? In both instances, it is Jesus who is Lord of the sabbath. He is the one authorized to overrule even Moses (Torah). Matthew has already dwarfed the primacy of Moses earlier (chapter 5), when Jesus says repeatedly, (6 times) "You have heard it said, but I tell you..."
The question of God's needing rest is not tangential when it comes to the Ancient Near East. The fertility gods were worshiped by the Canaanites because they were thought to provide fruitful land. These gods hibernated during the winter and rose again in the beginning of the growing season. In an agrarian economy, having fertile land made it possible to settle and survive. The fertility god Baal,or Baalim mentioned throughout the Old Testament, is one such god of the land.
There is the story of Elijah and the prophets of Baal. (2) Elijah baits the false prophets, challenging them to call down Baal to strike the would-be sacrifice with fire. Elijah gives them a very long time mockingly noting that Baal may be meditating or resting. When nothing happens and it's Yahweh's "turn," the sacrifice becomes a cinder. The false prophets meet a gruesome end. Yahweh is the one who "neither slumbers or sleeps."
Here I am addressing the theology of sabbath, what it says about God as different from us. God is God, the ruler of heaven and earth, Lord of all the powers of the universe. God does not grow faint or weary. Regarding the sabbath, one can believe in its importance for all creation without God literally lying down and taking a nap.
The institution of sabbath observance underlines the importance of all humankind and creation resting on the seventh day. It's about God giving us rest because we are not God. Further, we can rest chiefly because God is always at work. While God's creatures need sabbath, God does not.(1) I am indebted to the insights of Rowan Williams, Tokens of Trust, Westminster John Knox Press, 2007, especially p. 1-12.
(3) See Psalms 121:4.