A Listing of the Plagues:
1. Water turned to blood
2. Frogs
3. Gnats
4. Flies
5. Death of animals
6. Boils
7. Hail
8. Locusts
9. Darkness
10. Death of firstborn

In the first three plagues, Aaron was God's instrument, and the first two plagues were copied by Pharaoh's magicians.   Beginning with the fourth plague of flies, the area of Goshen was not affected.  Moses was God's instrument for plagues 6,7,8, and 9.  For plagues 4, 5, and 10, neither Moses nor Aaron are listed as being God's instruments in carrying out the plagues.

If all the livestock died during plague 5, what animals had boils in plague 6? It seems as if there is a difference  made between livestock and animals. Perhaps the animals with the boils were household animals or other animals not considered livestock.

After the plague of boils, Pharaoh doesn't harden his heart, it is God who hardens Pharaoh's heart.  We are reminded repeatedly that God has hardened Pharaoh's heart so that His (God's) power may be displayed.

During the plague of hail, again livestock is mentioned. Some time must have passed since plague 5 for them to have livestock or they could have acquired more animals from outside the city of Egypt and from the land of Egypt. (Egypt is the city. The land of Egypt is the surrounding fields and country.)

In Exodus 8:25, Pharaoh tells Moses they can sacrifice to God but to do it within the land. Moses responds with saying that sacrificing animals in the land would be an abomination to the Egyptians. What he means is that the very animals that the Hebrew people would be sacrificing are the animals that the Egyptians considered "gods".

Exodus 9 gives us a clue as to the time of year between plagues 7 and 8.  It is late spring because "the barley had headed and the flax was in bloom".

In Exodus 10 Moses says to Pharaoh, "we are to celebrate a festival to the Lord."  This is a festival yet to be identified to the Hebrew people.  We know it is Passover - part of the Feast of Unleavened Bread, which occurs in late spring.

The plague of locusts is a devastating phenomenon. The locusts destroy every green thing on tree or plant.

In the plague of darkness, it says that the darkness can be felt, yet all the Israelites had light in the places where they lived. What kind of darkness can be felt?  Praise God, that Jesus is our Light!

1 Pet 2:9
But you are a chosen people, a royal priesthood, a holy nation, a people belonging to God, that you may declare the praises of him who called you out of darkness into his wonderful light.