Behold, he comes up like clouds;
    his chariots like the whirlwind;
his horses are swifter than eagles—
    woe to us, for we are ruined!
O Jerusalem, wash your heart from evil,
    that you may be saved.
How long shall your wicked thoughts
    lodge within you?
For a voice declares from Dan
    and proclaims trouble from Mount Ephraim.
Warn the nations that he is coming;
    announce to Jerusalem,
“Besiegers come from a distant land;
    they shout against the cities of Judah.
Like keepers of a field are they against her all around,
    because she has rebelled against me,
declares the Lord.
Your ways and your deeds
    have brought this upon you.
This is your doom, and it is bitter;
    it has reached your very heart.” – Jeremiah 4:13-18 ESV

God was demanding change. He called them to repent and expected that repentance to entail more than just an external change in behavior. God knew that their real problem was much deeper than that. They suffered from a heart condition. Which is why God had Jeremiah warn them:

“O Jerusalem, cleanse your heart
    that you may be saved.
How long will you harbor
    your evil thoughts?” – Jeremiah 4:14 NLT

The day of their destruction was coming, like a fast-approaching storm, bringing devastation and destruction in the form of war horses and chariots. And if the people of Judah had any hopes of avoiding the inevitable outcome of a Babylonian invasion, they were going to have to cleanse their hearts. But was that even possible? And was God really expecting them to be able to do so? The prophet, Isaiah, who was also sent by God to warn the people of Judah regarding their wickedness and God’s impending judgment of them, had a very similar word from God:

Wash yourselves; make yourselves clean;
    remove the evil of your deeds from before my eyes;
cease to do evil,
    learn to do good;
seek justice,
    correct oppression;
bring justice to the fatherless,
    plead the widow's cause. – Isaiah 1:16-17 ESV

Notice what Isaiah writes. They were to wash themselves. They were to make themselves clean. It was up to them to get rid of their evil behavior and to start doing what God commanded. Their purification was to have external proofs that they had indeed changed. But again, was what God demanded of them even possible? Could they purify themselves? Well, the next verse gives us the answer:

“Come now, let us reason together, says the Lord:
though your sins are like scarlet,
    they shall be as white as snow;
though they are red like crimson,
    they shall become like wool.” – Isaiah 1:16-18 ESV

It was as if God said, “Let’s think about this.” Their ability to purify their own hearts was non-existent. They were incapable of changing their ways – on their own. If fact, later on, in the book of Jeremiah, God makes the following assessment of their ability to change:

You will probably ask yourself,
‘Why have these things happened to me?
Why have I been treated like a disgraced adulteress
whose skirt has been torn off and her limbs exposed?’
It is because you have sinned so much.
But there is little hope for you ever doing good,
you who are so accustomed to doing evil.
Can an Ethiopian change the color of his skin?
Can a leopard remove its spots? – Jeremiah 13:22-23 NLT

Their predilection to sin was ingrained, a part of their DNA. Like every other human being, they had inherited the sin nature of Adam. Disobedience to God came naturally. A propensity toward evil was built into them. They could no more change their nature than a leopard could remove its spots. Like a person’s genetic makeup determines their skin color, the people of Judah had a built-in predisposition toward sin. But God was also telling them that He was willing and able to do something about their condition. He lets them know that even though they have been stained by their sins, He can make them white as snow. He has the ability to wash them clean from all their iniquities and make them pure. Isaiah wrote these words of God to the people of Judah:

“I, I am he who blots out your transgressions for my own sake,
    and I will not remember your sins.” – Isaiah 43:25 ESV

God would remove their sins, not because they deserved it, but simply because He wanted to show His grace and mercy. They would not be able to earn His forgiveness through human effort, but God did expect them to turn back to Him and acknowledge their need for Him. Like the great king David, they would have to call out to God and ask Him to do for them what they could not do for themselves.

Purify me from my sins, and I will be clean, wash me, and I will be whiter than snow. – Psalm 51:7 NLT

It is only when we come to grips with our own incapacity to redeem ourselves, that we turn to God as our redeemer. When we finally realize that we are incapable of improving our own behavior and cleaning up our act, that is when we become desperate enough to call on Him. But for some reason, we stubbornly hold on to the idea that we can change ourselves. We mistakenly cling to the hope that we can muster up enough strength to do enough good things that will earn us favor with God and hold off His punishment of us. But just a few verses later, Jeremiah writes this painful assessment of the people of Judah:

“My people are foolish
    and do not know me,” says the Lord.
“They are stupid children
    who have no understanding.
They are clever enough at doing wrong,
    but they have no idea how to do right!” – Jeremiah 4:22 NLT

Once again, the prophet Isaiah makes a chilling assessment of Judah’s complete inability to mend their hearts and change their behavior.

You assist those who delight in doing what is right,
who observe your commandments.
Look, you were angry because we violated them continually.
How then can we be saved?
We are all like one who is unclean,
all our so-called righteous acts are like a menstrual rag in your sight.
We all wither like a leaf;
our sins carry us away like the wind. – Isaiah 64:5-6 NET

Isaiah seems to be saying that God comes to the aid of those who long to do what is right, what God demands. But the problem is that those very same people can’t turn their delight into action. Even their most righteous actions end up looking like bloody rags before God. They are completely controlled by the sin in their lives. They want to do what is right, but lack the capacity to turn their desires into reality. The apostle Paul described having a similar frustration:

I don’t really understand myself, for I want to do what is right, but I don’t do it. Instead, I do what I hate. But if I know that what I am doing is wrong, this shows that I agree that the law is good. So I am not the one doing wrong; it is sin living in me that does it.

And I know that nothing good lives in me, that is, in my sinful nature. I want to do what is right, but I can’t. I want to do what is good, but I don’t. I don’t want to do what is wrong, but I do it anyway. But if I do what I don’t want to do, I am not really the one doing wrong; it is sin living in me that does it. I have discovered this principle of life—that when I want to do what is right, I inevitably do what is wrong. – Romans 7:15-21 NLT

Paul fully realized that, if left to himself, he was incapable of doing what he really wanted to do. In the flesh, he couldn’t produce the kind of life God demanded. He could desire it, but his sin nature would fight him every step of the way. So, Paul cried out:

Oh, what a miserable person I am! Who will free me from this life that is dominated by sin and death? Thank God! The answer is in Jesus Christ our Lord. – Romans 7:24-25 NLT

Paul knew His hope was external, not internal. His Savior was Christ, not himself. He needed Jesus Christ to do for him what he could not do himself. And the people of Judah would have to reach the same conclusion. They would have to turn to God for their salvation, but also for their cleansing. In fact, they were going to need to desire cleansing more than salvation. While they all wanted to avoid the coming destruction, they weren’t all that keen on changing their behavior. They wanted God’s salvation, but didn’t seem to think they were so sinful that they needed His cleansing. But God wanted them to grieve over their sins. He wanted them recognize their sinfulness and their own inability to do anything about it. Then they would turn to Him for help. King David learned that very lesson after having sinned against God by having an adulterous affair with Bathsheba, then having her husband eliminated so he could marry her. He recognized His sin against God and realized that what God wanted was a broken and repentant spirit.

For you will not delight in sacrifice, or I would give it;
    you will not be pleased with a burnt offering.
The sacrifices of God are a broken spirit;
    a broken and contrite heart, O God, you will not despise. – Psalm 51:16-17 ESV

And it was his own brokenness and his recognition of his complete dependence on God to purify him that led David to write:

Wash me thoroughly from my iniquity,
    and cleanse me from my sin! – Psalm 51:2 ESV

And the sad indictment God made against the people of Judah was that their sin had permeated them to the very core of their being. Their hearts were stained by their wickedness. In fact, their wickedness was a byproduct of their sin-filled hearts. Which is why God said:

“Your ways and your deeds
    have brought this upon you.
This is your doom, and it is bitter;
    it has reached your very heart.” – Jeremiah 4:18 ESV

They would need God to do for them what they could not do for themselves. But first they would need to turn to Him. They would need to rely on Him for the power to cleanse and forgive.

English Standard Version (ESV)
The Holy Bible, English Standard Version. ESV® Permanent Text Edition® (2016). Copyright © 2001 by Crossway Bibles, a publishing ministry of Good News Publishers.

New Living Translation (NLT)
Holy Bible, New Living Translation, copyright © 1996, 2004, 2015 by Tyndale House Foundation. Used by permission of Tyndale House Publishers Inc., Carol Stream, Illinois 60188. All rights reserved.

The Message (MSG)Copyright © 1993, 1994, 1995, 1996, 2000, 2001, 2002 by Eugene H. Peterson