And it came to be at midnight that יהוה smote all the first-born in the land of Mitsrayim, from the first-born of Pharaoh who sat on his throne to the first-born of the captive who was in the dungeon, and all the first-born of livestock.
“And I shall harden the heart of Pharaoh, and he shall pursue them. But I am to be esteemed through Pharaoh and over all his army, and the Mitsrites shall know that I am יהוה.” And they did so.
So Mosheh and Aharon went in to Pharaoh, and they did so, as יהוה commanded. And Aharon threw his rod before Pharaoh and before his servants, and it became a serpent.