Three months after the Exodus, Israel was at Sinai.
Nine months later, the tabernacle was set up, and they celebrate Passover at Sinai before moving out. God provides for an alternate feast a month later, if you're unclean and can't celebrate at the usual time.
The cloud and fire will move and direct Israel when to move and where to go.
Trumpets will signal when to break camp, or gather the Chiefs, or gather the whole nation, or prepare for war.
Right after Passover the cloud lifts and they break camp according to the instructions. Moses asks Jethro to go, but it is unclear if he does.
Israel complains about the manna menu; Moses complains about the burdensome people.
God says to choose 70 elders to help Moses bear the burden. They gather and God Puts His Spirit on them, like on Moses (Pentecost!).
God provides quail, but also a plague on those who complained.
How this is about Jesus
He dealt with complainers and arguers, too! But He bore the burden of the people all alone, with the help of the Spirit.
Sins this reveals
We are quick to complain, slow to believe, and often want to rest when God calls us to march. Or we want to fight when God calls us to rest...