Exodus 32-34

At the beginning of Exodus 34 Moses is directed to carve out two stone tablets on which God would inscribe the words of the covenant. I wonder why God didn't make the first set unbreakable? Or why didn't he reassemble the stones that Moses shattered? What message was he sending to Moses, Israel, and us by requiring Moses to carve out another set of tablets? Was it to allow Moses to participate in the recording of the Law? Was it to give him ownership in the care of the tablets? Was it a way to show Israel that God can take what little we bring and make it holy, fitting for his purpose? Doesn't God do the same thing with us. When we break something God has given us he will call us to bring the closest thing we can find to him. And then he will imprint his word on our efforts of faith.
Stuart