The context of this passage is the Lord turning the Nile River to blood, the first plague against Pharaoh and Egypt. Moses delivered a message to Pharaoh from the Lord commanding him to let Israel go that they may worship the Lord. When Pharaoh refuses, the Lord sends this plague of blood that results in no drinking water and the death of the fish Egypt greatly depended upon.
The magicians of Pharaoh come and attempt an imitation of the miracle, but they cannot reverse the curse on the Nile which is what Pharaoh needed them to do. The futility of their efforts is seen in verse 24 when we are told that the Egyptian people are frantically digging new wells in search of water.
The stark contrast in people is made plain for our instruction. We are told Moses and Aaron did all the Lord told them to do, demonstrating humble submission despite a hard task given to them to confront opposition such as Pharaoh. Pharaoh, on the other hand, when seeing the awful nature of the plague and the powerlessness of any resource he had to reverse it, simply turns his back on it all, and goes back into his house. His heart is hardened.
One of the favorite illustrations of the Puritans concerned how people respond to the Word of God. They used the effects the sun has on different objects to make the point. The sun melts some substances, such as wax; yet it hardens other substances, such as clay. You have the same agent, the sun, yielding a completely different outcome.
The same is true of the Word of God on people when they hear it. For some it means a response of humility, faith, and worship. For others it means hardening and resistance. The Scriptures teach us that it is the tendency of the sinful hearts of men to be hardened under the Word of God. There is no neutrality. To not rightly respond is to refuse God.
Pharaoh was a pagan, idolatrous king with tremendous wealth and power. In his eyes he had too much to lose to submit to the Lord’s command. Even though the Lord’s power was made plain to him, he grew harder in heart.
It isn’t just people in Pharaoh’s position, however. Jesus told the Jewish crowds in Galilee that thought they witnessed him doing great signs (the miracles he did) and heard his word, they would not repent. They also felt they had too much to lose to humble themselves under the Lord’s Word. Like Pharaoh, they lost their lives in resisting the Lord (Matthew 11, John chapters 11-12 for example).
We need to learn, each responsible for themselves, what the Scripture says is vital. We are taught by the Lord that we have two primary problems that outweigh any needs or other problems no matter what they are.
The first is a problem of guilt. We have a legal problem with God. Our sin seems normal to us. It is not treated that way by God. Every sin in heart, word, and deed incurs a debt. It is owed justice from God. This truth lies behind the reason men put Jesus to death. Jesus said it was what is inside a man that makes him unclean, and He only could make men clean.
None of us can do anything about our debt of sin. This is why the gospel is good news. Jesus paid in full the debt of sin on the cross. His death and his righteousness are freely given by God to whoever truly believes in him. He is perfectly sufficient for our guilt problem.
The other problem is our nature. Our heart inclines us to flatter ourselves too much to detect our sin (Psalm 36). As we have already observed, sin is what causes us to resist the Word of God. There is no one different. We are all the same in this. Without God’s grace we will not humble ourselves before God or believe in Christ. We have great need of God giving us aid.
God also meets this need by giving the Holy Spirit to us. However you came to faith in Christ, you owe God the glory in being a believer, and the humble thanksgiving that reflects an acknowledgment of grace, as well as continuing to rightly respond to God’s Word. If you don’t know Christ, you should simply ask God for mercy and forgiveness, and stop resisting the Lord.