In the Babylonian Talmud (M'nachot 29b) there is a wonderful midrash1 in which Moses is depicted as watching God sitting and writing crowns (embellishments that look a bit like crowns) on some of the letters in the Torah. Moses asked God why the Holy One was doing this.
The last instruction that Moses receives on Mount Sinai, before God gives him the inscribed tablets, before the incident of the Golden Calf, is the reminder about the importance of the sabbath.
This week's Torah portion contains one of the most dramatic events in the entire Torah, the incident of the Golden Calf. Moses has been on Mount Sinai for a very long time, too long for those Israelites who still carry Egypt in their hearts to wait.