Israel had defiantly disobeyed one of God’s clear commands. They were God’s son, yet when Moses took so long to come down from Sinai they set up the golden calf. God judged them and consequently Moses and the people were afraid God would withdraw himself from them. But he did not. Moses is assured of God's love, and is allowed to see God's glory. In the cleft of the rock Moses sees God's goodness, grace, and greatness.
Read Exodus 33