In Exodus 31 & 32, God appoints the people who will be the craftsmen in charge of building the Tabernacle and all the things He commanded to be made. He then reminds them they must rest. They must not dishonor the Sabbath and need to stop working to rest and replenish. The Israelite people were held captive for over 400 years in a pagan culture filled with idol worship. They were not used to a God who couldn't be seen regularly and had to be worshiped in faith, trust, and patience. They got impatient waiting for Moses' return and built an idol. Just 40 days after God had spoken with them and they promised to keep His commands. Moses has compassion and contends for Israel but it's really God who is the source of this compassion. God is doing a work in Moses through this so he could understand God's desires of both compassion to those who follow Him as well as judgment and accountability for those who choose not to. Much like Jesus, Moses offers to have his name removed from God's record of eternal life to take the place of the rest of Israel.  Moses was a child of God and God declined the offer. Moses' name was written into God's story just like our names are when we accept Jesus as our Savior. We are forever written into God's record - His eternal story.