The word plague means ‘a blow, a stroke,’ and indicates that the hand of the Lord was punishing the Egyptians. The longer Pharaoh resisted God, the more serious the judgments became.” – Warren W. Wiersbe
While the first three plagues were unnerving (water to blood, frogs, gnats), the second three were wounding and costly (flies, death of livestock, boils).
You may read Exodus 9:1-12 here: Bible Gateway. The following is my fictional piece.
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Pharaoh pace as he wait for his magi. The flies had vanished after Moses prayed to his god. But the threat from Moses and Aaron a couple of days ago about a deadly pestilence struck full force yesterday. Not only did the cattle of the fields die, but also the horses, donkeys, camels, and sheep that grazed in the pastures.
The most disturbing part, not a single beast from the Israelite clan contracted this deadly disease.
Pharaoh scratched his head. Had he offended his gods? He had never missed Opet’s great festival. Hadn’t he always revered Thoth, Ounnefer, Re, and Atum?
Why is mighty Apis allowing this cattle plague? Who is this desert deity that Moses keeps referring to as Lord? And why would he side with these low class slave people?
“Sir,” Pharaoh didn’t notice the servant entering the throne room. “We could only bring in one magi . . .”
“Ridiculous!” Pharaoh interrupted. “Where are the others? Bring them at once!”
The servant elbowed the magi forward—avoiding physical contact as much as possible—but the magi collapse to the floor. Pharaoh gagged. Who is this man? He resemble more of a writhing snake about to shed his dry skin. Wet yellow pus seep from his scaly blisters. Red bumps cover his entire body. His puffy eyes were swollen shut.
“Take him!” He pointed to the door. “Wh-what happened to him?”
“Sir, Moses scattered ashes into the air . . .”
“I know, he did it in my presence!”
“That’s when this dreaded disease came upon both the people and the animals.”
“Are the Israelites affected?”
“No Sir. I am told that none of the Israelites, or their animals, are suffering.”
Hmph! Who does Moses think he is . . . messing with a god like me?!
Pharaoh squeezed his servant’s arm hard. With flared nostrils, he shouted, “Tell Moses that I still refuse him and his hideous people passage to worship their god in the desert!”
Reflect
I love to focus on God’s love and mercy. But the truth is, God’s righteous character also includes anger and judgment. Proverbs 29:1 says, “Whoever remains stiff-necked after many rebukes will suddenly be destroyed—without remedy.”
Even though the Egyptians were greatly suffering, Pharaoh continued in stubborn resistance to God and God’s servants.

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The fear of God is the opposite of a hardened heart. Reverential fear and respect motivates us to obey God’s commands (Prov. 9:10).
The NIV Life Application Study Bible notes: God gave Pharaoh many opportunities to heed Moses’ warnings. But finally God seemed to say, ‘All right Pharaoh, have it your way,’ and Pharaoh’s heart became permanently hardened. Did God intentionally harden Pharaoh’s heart and overrule his free will? No, he simply confirmed that Pharaoh freely chose a life of resisting God. Similarly, after a lifetime of resisting God, you may find it impossible to turn to Him. Don’t wait until just the right time before turning to God. Do it now while you still have the chance. If you continually ignore God’s voice, eventually you will be unable to hear it at all.”