Exodus 34 shows us something spectacular and unappreciated about the religion of Moses.
First, Moses' ascension to the mountain (he spends 40 days fasting in the presence of the Lord) results in him having the appearance of God. In his descent, he shines.
Second, in Moses' time on the mountain, he performs the tasks that God performs. The first time around, God speaks the ten commandments and then He writes them with His own finger. When He invites Moses up, God says that God will write the commandments again. Then, in what seems like a craftsman's apprenticeship, Moses remains in the presence of the Lord and writes the commandments himself.
On the mountain, Moses becomes divine. Does this shed light on Jesus' 40 days fasting in the wilderness?