Exodus 7:13-15

Young's Literal Translation

¹³ and the heart of Pharaoh is strong, and he hath not hearkened unto them, as Jehovah hath spoken.

¹⁴ And Jehovah saith unto Moses, `The heart of Pharaoh hath been hard, he hath refused to send the people away;

¹⁵ go unto Pharaoh in the morning, lo, he is going out to the water, and thou hast stood to meet him by the edge of the River, and the rod which was turned to a serpent thou dost take in thy hand,