Chp. 7 verses 1 - 23; Hashem tells Moshe that Aaron would be his interpreter. Also that He would harden Pharaoh's heart and he would not listen to them, so that Egypt would know that it was G-d who would take the Jews out of Egypt. Aaron performs wonders before Pharaoh, but his magicians duplicate his acts. Moshe then warns Pharaoh and brings the first plague of blood. The magicians duplicate the feat, Pharaoh refuses to let the Jews go sacrifice to their G-d.