God used Moses to deliver His people from oppressive slavery in Egypt. Pharoah’s heart was hardened so God sent ten plagues of hardship to Egypt. The first was turning the water of the Nile River into blood.

Exodus 7:

20 So Moses and Aaron did just as the Lord commanded them. As Pharaoh and all of his officials watched, Aaron raised his staff and struck the water of the Nile. Suddenly, the whole river turned to blood! 21 The fish in the river died, and the water became so foul that the Egyptians couldn’t drink it. There was blood everywhere throughout the land of Egypt. 22 But again the magicians of Egypt used their magic, and they, too, turned water into blood. So Pharaoh’s heart remained hard. He refused to listen to Moses and Aaron, just as the Lord had predicted. 23 Pharaoh returned to his palace and put the whole thing out of his mind. 24 Then all the Egyptians dug along the riverbank to find drinking water, for they couldn’t drink the water from the Nile.

25 Seven days passed from the time the Lord struck the Nile.