"Go and assemble the elders of Israel and say to them: the Lord, the God of your fathers, the God of Abraham, Isaac, and Jacob, has appeared to me and said, 'I have taken note of you and of what is being done to you in Egypt, and I have declared: I will take you out of the misery of Egypt to the land of the Canaanites, the Hittites, the Amorites, the Perizzites, the Hivites, and the Jebusites, to a land flowing with milk and honey.' They will listen to you; then you shall go with the elders of Israel to the king of Egypt and you shall say to him, 'The Lord, the God of the Hebrews, manifested Himself to us. Now therefore, let us go a distance of three days into the wilderness to sacrifice to the Lord our God.' Yet I know that the king of Egypt will let you go only because of a greater might. So I will stretch out My hand and smite Egypt with various wonders which I will work upon them; after that he shall let you go. And I will dispose the Egyptians favorably toward this people, so that when you go, you will not go away empty-handed. Each woman shall borrow from her neighbor and the lodger in her house objects of silver and gold, and clothing, and you shall put these on your sons and daughters, thus stripping the Egyptians."
But Moses spoke up and said, "What if they do not believe me and do not listen to me, but say: The Lord did not appear to you?" The Lord said to him, "What is that in your hand?" And he replied, "A rod." He said, "Cast it on the ground." He cast it on the ground and it became a snake; and Moses recoiled from it. Then the Lord said to Moses, "Put out your hand and grasp it by the tail"--he put out his hand and seized it, and it became a rod in his hand--"that they may believe that the Lord, the God of their fathers, the God of Abraham, the God of Isaac, and the God of Jacob, did appear to you."
The Lord said to him further, "Put your hand into your bosom." He put his hand into his bosom; and when he took it out, his hand was encrusted with snowy scales! And He said, "Put your hand back into your bosom." He put his hand back into his bosom; and when he took it out of his bosom, there it was again like the rest of his body. "And if they do not believe you or pay heed to the first sign, they will believe the second. And if they are not convinced by both these signs and still do not heed you, take some water from the Nile and pour it on the dry ground, and it--the water that you take from the Nile--will turn to blood on the dry ground."
But Moses said to the Lord, "Please, O Lord, I have never been a man of words, either in times past or now that You have spoken to Your servant; I am slow of speech and slow of tongue." And the Lord said to him, "Who gives man speech? Who makes him dumb or deaf, seeing or blind? Is it not I, the Lord? Now go, and I will be with you as you speak and will instruct you what to say." But he said, "Please, O Lord, make someone else Your agent." The Lord became angry with Moses, and He said, "There is your brother Aaron the Levite. He, I know, speaks readily. Even now he is setting out to meet you, and he will be happy to see you. You shall speak to him and put the words in his mouth--I will be with you and with him as you speak, and tell both of you what to do--and he shall speak for you to the people. Thus he shall serve as your spokesman, with you playing the role of God to him, and take with you this rod, with which you shall perform the signs."