In Exodus 6, God tells Moses that Pharaoh will eventually let the Israelites go because of His "mighty hand". God tells Moses to remind the Israelites of the covenant He established with them, saying "I will free you from being slaves, ...redeem you with an outstretched arm and mighty acts of judgment, .. will take you as my own people, and I will be your God... I will bring you to the land I swore to Abraham... I will give it to you as a possession. " But, the Israelites "did not listen because of their discouragement and cruel bondage. Moses asked the Lord why Pharaoh would listen to him , since not even the Israelites would listen to him "since I speak with faltering lips". In Exodus 7, the Lord encourages Moses, saying that He will make him like God to Pharaoh, and Aaron will be his prophet, both speaking everything to Pharaoh that the Lord commands. The Lord showed a sign to Pharaoh and his officials, through a miracle of making Aaron's staff become a snake when he threw it down to the ground. Still, Pharaoh's heart became hard and he would listen. So, next God sent Moses to meet Pharaoh by the water and give him this message " until now you have not listened.. By this you will know that I am the Lord" and Moses will strike the water of the Nile with his staff and it will become blood, killing the fish and making the water undrinkable. Aaron was told to do the same with his staff and all the remaining water in the streams, canals, ponds, reservoirs, buckets and jars will also become blood. Moses and Aaron did just as the Lord had commanded. But, Pharaoh's heart became hard again, and he would not listen to Moses and Aaron.