I am the Load in this land

Exodus 8:20-32
The fifth plagues of Flies
God make a distinction between God's people and Pharaoh's people. So that Egyptian will know that I, the Load, am in this land.
Load said to Moses, "Get up early in the morning and confront Pharaoh as he goes to the water and say to him"-- The time & place say to Pharaoh.
Throughout Egypt the land was ruined by the flies.
The sacrifices Israelite offer the Load would be detestable to the Egyptians.
Pharaoh allowed them sacrifice to The Load, but after the fly done, Pharaoh hardened his heart and would not let the people go also.
Why?
Sacrifices is detestable to Egyptian, so as Flies are detestable to Egyptian.
The Load make distinction between his people and people are not belong to him. One have mercy, others has plagues.
Pharaoh during the suffering he promised, but when it was relieved he regret and hardened his heart again.
Egyptian sacrifice their god by vegetable only, bull & sheep are holy stock to Egyptian.
How?
Can I live in the world make distinction between christian and non christian? I will do my best and need God's strength and mercy.
God is the Load in whole of the world.