So that the hebrews first children wont die God told them to kill a lamb and wipe its blood on their door. This way the angel of death would know to pass over their door. This is why jewish people celebrate the pass over.
If he will not let my people go I will send plagues until he lets them go
1. water to blood
3. Lice
4. Flies
2. frogs
5. death of live stock
x
8. Locusts
6. Boils
9. 3 days of darkness
7. fire thunderstorms
10. plague death of first child
your people can go
As God's chosen people were let go Moses was taking them to the promise land