Exodus 7:22-24

Young's Literal Translation

²² And the scribes of Egypt do so with their flashings, and the heart of Pharaoh is strong, and he hath not hearkened unto them, as Jehovah hath spoken,

²³ and Pharaoh turneth and goeth in unto his house, and hath not set his heart even to this;

²⁴ and all the Egyptians seek water round about the river to drink, for they have not been able to drink of the waters of the River.