Most people meet this question in Exodus, and they meet it as an accusation. God is about to send Moses back into Egypt, and before a single plague has fallen, before Pharaoh has said one word, God says this:

Exodus 4:21 (NKJV)

And the LORD said to Moses, “When you go back to Egypt, see that you do all those wonders before Pharaoh which I have put in your hand. But I will harden his heart, so that he will not let the people go.”

If we look at the entire book of Exodus and not simply this verse in isolation, we will see two very prominent things. Ten times we are told that God hardened Pharaoh's heart (4:21; 7:3; 9:12; 10:1, 20, 27; 11:10; 14:4, 8, 17). Ten times we are told that Pharaoh hardened his own (7:13–14, 22; 8:15, 19, 32; 9:7, 34–35; 13:15).

Exodus 8:32 (NKJV)

But Pharaoh hardened his heart at this time also; neither would he let the people go.

Notice that the writer of Exodus is not troubled by this. He is not trying to reconcile the two, or slip one past us while we are looking at the other. He sets them side by side, because both are true.

God did not make a good man wicked

God did not reach into a tender heart and turn it to stone. He did not pour cruelty into a man who had none. Look at Pharaoh before any hardening is mentioned in the story. Moses comes with the word of the LORD, and this is the answer he gets:

Exodus 5:2 (NKJV)

And Pharaoh said, “Who is the LORD, that I should obey His voice to let Israel go? I do not know the LORD, nor will I let Israel go.”

That is not a man who needed corrupting. That is a slave-master who had built his throne on the backs of a whole nation, who had ordered Hebrew boys drowned in the river, and whose settled conviction was that no one in heaven or earth outranked him. When the plagues came, Pharaoh did not do anything he did not want to do. He was never dragged. He was never overruled. At every point he did precisely what he most wanted, and what he most wanted was his own way.

This is how Scripture speaks of hardening in one simple sense — God letting go. Three times in Romans 1, Paul describes God's judgment on a world that will not have Him, and each time the verb is the same: God gave them up. He gave them up to their uncleanness, to their passions, to a debased mind — that is, He handed them over to themselves. He stopped holding them back. And when God stops holding a man back, that man does not become someone else. He becomes, at last, entirely himself.

That is the first half of the answer. Every restraint Pharaoh ever felt — every twinge of conscience, every hesitation, every moment when he nearly relented — was God's mercy holding him in check. When God withdrew that mercy, He did not add one grain of wickedness to Pharaoh's heart. He simply took His hand off a man who had spent his life straining against it.

But God meant it, and He said so in advance

Now we must be honest about the part that is harder to swallow, because a great many writers stop at the paragraph above and leave the reader with the impression that God merely stood by. He did not merely stand by. He announced the hardening before it happened (4:21), and He tells us plainly what He was doing it for:

Exodus 14:4 (NKJV)

“Then I will harden Pharaoh's heart, so that he will pursue them; and I will gain honor over Pharaoh and over all his army, that the Egyptians may know that I am the LORD.” And they did so.

There is the why, and Paul repeats it centuries later, quoting God's own words to Pharaoh as the settled explanation of the whole affair:

Romans 9:17–18 (NKJV)

For the Scripture says to the Pharaoh, “For this very purpose I have raised you up, that I may show My power in you, and that My name may be declared in all the earth.” Therefore He has mercy on whom He wills, and whom He wills He hardens.

So the answer to the question is this: God hardens hearts in order to display His power and make His name known in all the earth. Pharaoh's hardness was not an obstacle God had to work around; it was the very thing through which God worked.

Every refusal set up another plague. Every plague brought down another Egyptian god — the Nile, the sun, the cattle, the firstborn heir — until the greatest empire on earth had been dismantled in public by the God of a slave people. Had Pharaoh let Israel go after the first plague, there would have been no Red Sea. There would have been no song on the far shore. There would have been no story for Israel to tell its children for the next three thousand years.

Why could Pharaoh watch the Nile turn to blood and still say no?

People often ask how any man could see the miracles Pharaoh saw and refuse to bend. But that assumes evidence softens hearts. It does not. Pharaoh had made up his mind before the first plague fell — I do not know the LORD, nor will I let Israel go — and a made-up mind is not moved by facts. It is only confirmed by them.

Do not mistake what happened after the last plague. Pharaoh did not repent when his son died. He surrendered, which is not the same thing, and within days he had changed his mind again and was chasing Israel across the desert with six hundred chariots. Catastrophe did not melt that heart. It only revealed how cold it had gone. This is what hardening does.

The Bible asks the same of us today

Hebrews 3:15 (NKJV)

while it is said: “Today, if you will hear His voice, do not harden your hearts as in the rebellion.”

Today. The warning is not aimed at Egyptians three thousand years ago. It is aimed at the reader, and its urgency comes from the fact that hardening is progressive. Every time God's voice is heard and set aside, the ear grows a little duller. No one chooses, on a particular morning, to become a man who cannot repent. He simply says “not yet” often enough, and one day finds that “not yet” has become “cannot.”

And here we must be careful, because the natural thing to say next is: so soften your heart. But that is precisely what a heart of stone cannot do. Stone does not decide to become flesh. If Pharaoh's own strength could not save him, ours will not save us either; and if the softening of a heart were finally our work, then Hebrews would be handing us an instruction we have no power to carry out.

So God does not hand us an instruction. He makes a promise:

Ezekiel 36:26 (NKJV)

I will give you a new heart and put a new spirit within you; I will take the heart of stone out of your flesh and give you a heart of flesh.

Read who is doing the work in that verse. I will give. I will put. I will take out. Every verb belongs to God. The same sovereign hand that withdrew from Pharaoh and left him to himself is the hand that reaches into a dead man's chest and puts a living heart there — and it is not owed to anyone. It is mercy, and mercy by definition is never earned.

Genesis 22 is the passage people throw down as their trump card against the God of the Old Testament. Here God tells Abraham to take Isaac — the son he waited a lifetime for, the son the promise itself depended on — up a mountain and kill him.

Genesis 22:2 (NKJV)

Then He said, “Take now your son, your only son Isaac, whom you love, and go to the land of Moriah, and offer him there as a burnt offering on one of the mountains of which I shall tell you.”

Let's just speak of the plain fact before we go any further into this conversation. The simple truth is that it did not happen. God stopped it. The knife never came down. And He did not stop it at the last moment because He had changed His mind, or because Abraham had talked Him out of it. He stopped it because it was never going to happen — because a ram was already caught in a thicket on that mountain, providentially put there by God.

Interestingly, you can also see a glimpse of Abraham's faith that God had a plan in place even before they went up the mountain. He told his young men:

Genesis 22:5 (NKJV)

And Abraham said to his young men, “Stay here with the donkey; the lad and I will go yonder and worship, and we will come back to you.”

Notice what he says: “we will come back.” Not I. This indicates that even Abraham had faith that God could raise up his promised son if necessary.

When Isaac — carrying the wood on his own back (which should tell us something all by itself) — asks his father where the lamb is, Abraham answers:

Genesis 22:8 (NKJV)

And Abraham said, “My son, God will provide for Himself the lamb for a burnt offering.” So the two of them went together.

We would assume that the man climbing that hill was numb, or broken, or blindly obedient. He was none of those things. The New Testament tells us what was going on in the man's mind:

Hebrews 11:17–19 (NKJV)

By faith Abraham, when he was tested, offered up Isaac, and he who had received the promises offered up his only begotten son, of whom it was said, “In Isaac your seed shall be called,” concluding that God was able to raise him up, even from the dead, from which he also received him in a figurative sense.

Here was a man holding God's promise in one hand and God's command in the other, unable to see how both could be true — and he trusted God's character enough to conclude that if Isaac died, God would raise him. He obeyed because he believed God would keep His word. He was not a father who had made peace with losing his son. He was a father who had decided God could not lose him.

And at the top of the mountain, God speaks:

Genesis 22:12–13 (NKJV)

And He said, “Do not lay your hand on the lad, or do anything to him; for now I know that you fear God, since you have not withheld your son, your only son, from Me.” Then Abraham lifted his eyes and looked, and there behind him was a ram caught in a thicket by its horns. So Abraham went and took the ram, and offered it up for a burnt offering instead of his son.

Instead of his son. That is the sentence the whole chapter was building up toward, and it is the answer to the question we started with. The nations around Abraham fed their children to their gods. Israel's God stopped the hand of the one man who was willing, and put an animal in the boy's place. And when the Law came, He said it in words no one could soften — the thing the nations did for their gods was the thing He hated, an abomination He never commanded and that never entered His mind (Deuteronomy 12:31; Jeremiah 32:35). God never wanted the boy dead. He wanted a father who would trust Him with the boy, and then He provided the substitute Himself.

Which is why Genesis 22 is not finally about a knife withheld. It is about a substitute given — and about a mountain God was pointing to the whole time.

Centuries later, on a hill in that same country, another Father brought His only Son up the slope, and the Son carried the wood on His own back. That time, no voice called from heaven. No ram was found in the thicket. The knife did not stop, because there was no substitute left to find — the Son was the substitute, and the debt was His to pay.

Romans 8:32 (NKJV)

He who did not spare His own Son, but delivered Him up for us all, how shall He not with Him also freely give us all things?

God did not spare His own Son so that He could spare us. On Moriah He gave a ram in the place of a boy; at Calvary He gave His Son in the place of His people. So the answer to the question is a firm no — God does not command human sacrifice. Rather, He gave His own incarnate Son as the sacrifice, for the benefit of everyone who will turn from their sin to Him.