Jesus, Sin, And The Reprobate Mind: Reading 1 John 1:8-10 From The Inside Out

She loves worship.

She cries when the band sings about the cross. She fills journals with Bible notes. She serves in church, smiles in the lobby, and knows the right phrases.

But when she goes home, she opens that same secret website again. Or messages that same person. Or reaches for that bottle. Or keeps replaying the same bitter story in her head.

Later, in the quiet, one question pounds in her chest:
“Is God even in me, or am I just fooling myself?”

If you have ever asked that, this is for you.

In this post we will look at 1 John 1:8-10 in the original Greek, connect it to Jesus as the Truth and the Word of God, and then wrestle with hard questions. What about a reprobate mind? What about people who seem very religious but live in secret sin? Are the people in Matthew 7:21 the ones who never had Jesus in them, or could they be church people who went hard in some areas and cold in others?

We will keep the language simple and the tone honest. We will talk about real things: porn, lying, greed, gossip, addiction, bitterness, fake religion. We will not just share opinions. We will work with Scripture in context and listen to the original words God gave us.

Before we start, a few quick definitions in plain language:

• Sin: anything in thought, word, or action that goes against God’s will and character.
• Truth: reality as God sees it, not just what we feel.
• Word: both Scripture and Jesus himself, the living Word of God.
• Reprobate mind: a mind that has been given over to stubborn sin and cannot see clearly anymore in that area.
• Conscience: the inner sense of right and wrong that can be soft, dull, or even burned.

Let’s watch how 1 John 1:8-10 opens this up.

---

Reading 1 John 1:8-10 In Context: Who John Was Talking To And Why It Matters

First, context. 1 John is a letter to believers who already know Jesus. These are Christians, not outsiders. But they are confused.

Some teachers had started saying strange things. Some denied that sin was a problem. Some acted like they had special knowledge that put them above normal believers. John steps in as an old, trusted pastor and writes to protect his “little children.”

In 1 John 1:5–2:2, the flow looks like this:

• God is light, and in Him there is no darkness at all.
• If we claim to walk with Him but walk in darkness, we lie.
• If we walk in the light, we have fellowship, and the blood of Jesus cleanses us.
• If we say we do not have sin, we lie and the truth is not in us.
• If we confess our sins, He forgives and cleanses.
• If we say we have never sinned, we make God a liar and His Word is not in us.
• When we do sin, we have an Advocate, Jesus Christ the righteous.

John is not giving permission to live in sin. He is attacking fake holiness and denial. He is saying, in simple terms: “Stop lying about your sin. Walk in the light. Confess. Jesus is enough.”

The same John also wrote the Gospel of John, where Jesus is called:

• The Word (Greek: logos) in John 1:1-3,14.
• The Truth in John 14:6.

So when John says “The Truth is not in us” or “His Word is not in us,” he is not making a cold doctrinal point. He is saying something very personal. Jesus Himself, the Word and the Truth, is not ruling inside a person who lives in denial.

There is a difference between:

• A believer who fights sin, confesses, and keeps walking in the light.
• A person who makes peace with sin, hides it, protects it, and lives in darkness.

If you want to go deeper into surrender, some find it helpful to read teaching on repentance and revival to see what honest turning to God looks like in a whole life.

A Simple Summary Of 1 John 1:8-10 Before We Go Deep

Let’s restate the passage in simple words.

1 John 1:8
“If we say we do not have sin, we are lying to ourselves, and the truth is not inside us.”

1 John 1:9
“If we admit and confess our sins, God is faithful and fair. He forgives our sins and washes us clean from all wrong.”

1 John 1:10
“If we say we have never sinned, we make God a liar, and His Word is not inside us.”

Notice the “we.” John includes himself. He is talking about believers. He expects believers to still battle sin, but he does not accept pretending that we are past it.

That short summary sets us up for the key Greek words.

Who Were The False Claims About Sin In John’s Day?

In John’s time, early forms of what later became Gnostic teaching were showing up.

Some people said things like:

• “We have no sin,” because they thought the spirit was pure and only the body was bad.
• Others thought that having “secret knowledge” made them spiritually above normal believers. They talked like sin did not touch them.

John cuts through that spiritual pride. He says, in effect, “If you say you have no sin, you are lying to yourself, and the truth is not in you.”

We see the same heart today:

• “I am a good person. I do not really sin.”
• “God understands. This is just who I am.”
• “I am under grace, so sin does not really matter.”

Different clothing, same disease. The problem is not only the sin itself, but the refusal to call it what God calls it.

---

Word Study: What 1 John 1:8-10 Really Says About Sin, Truth, And The Word In Us

Here are the key Greek words in this passage:

• Hamartia: sin, missing the mark.
• Alētheia: truth, reality as God sees it.
• Logos: word, message, and in John’s writings, also a title for Jesus.
• Homologeō: confess, say the same thing as God.
• Katharizō: cleanse, wash clean.
• Adikia: unrighteousness, injustice, wrongness.

These words pull us into the main idea: when someone chooses sin over God and lives in denial, The Truth and The Word are not living and ruling in that person. Not really.

“If We Say We Have No Sin”: What Hamartia Shows About Our Heart

Hamartia means “missing the mark.” It is picture language. An archer shoots at a target and misses. That is hamartia.

In 1 John 1:8, the word is singular: “sin.” This points to our fallen nature, our bent away from God. In 1 John 1:9, John switches to the plural “sins,” which points to the many actions that flow from that nature.

When we say “we have no sin,” we are not just wrong. We are proud and blind.

Think of a few examples:

• Someone lies to protect their image. They call it “being wise” or “managing the story.” That is sin, but they rename it.
• Someone uses porn night after night and calls it “stress relief.” That is sin, but they treat it like a health trick.
• A business owner squeezes employees and cheats taxes, but calls their greed “good stewardship.” That is sin, but now it has a holy label.

God says, “This is hamartia.” The person says, “No, this is normal.” Right there, the heart hardens.

If you want to see more study on this passage, some helpful Greek-based reflection can be found in articles like 1 John 1:8-10: Our Sin.

“We Deceive Ourselves” And “The Truth Is Not In Us”: Alētheia And Jesus As The Truth

When John writes, “we deceive ourselves,” he uses the verb planōmen. It means we wander, drift off, get led astray. We become our own false teacher.

Alētheia, “truth,” is not just facts. It is truth as God sees it, solid, uncovered, nothing hidden.

In John 14:6, Jesus says, “I am the way, and the truth, and the life.” He is not only a speaker of truth. He is Truth in person.

So when 1 John 1:8 says “the truth is not in us,” it hits deep. It is not only that we ignore facts. It is that the presence and rule of Jesus, the Truth, is not active in us.

Picture a house at night. When truth is in the house, lights are on and curtains are open. Dirt can be seen and cleaned. When someone denies sin, it is like they close the curtains, dim the lights, and insist, “This room is spotless,” while tripping over trash.

A pattern of denying sin is a sign that Jesus is not ruling that heart, even if the person looks holy in public.

“If We Confess Our Sins”: Homologeō, Agreement With God, And Real Repentance

The word for “confess” here is homologeō. It means “to say the same thing.” So real confession is not just “Sorry.” It is agreement with God.

We say what God says about our sin. We stop defending it. We stop softening it. We name it clearly.

John also uses two key words about God:

• Pistos (faithful). God can be trusted to respond the same way every time.
• Dikaios (just or righteous). God forgives in a way that fits His justice, because Jesus paid the price as our Advocate (1 John 2:1-2).

Then comes katharizō, “to cleanse.” God does not just cover our sin like paint on mold. He washes and purifies.

You see this in real-life confession:

• Someone finally tells a trusted friend about a long-term porn habit and asks for help, filters, and prayer.
• Someone admits hidden bitterness and chooses to forgive instead of rehearse the hurt.

If you want to see another study on confessing sin from 1 John, there is a helpful overview in Confessing Sin (1 John 1:8-9).

Regular confession keeps the heart soft. A soft heart is the opposite of a reprobate mind.

When you listen closely to Jesus, you see that confession is not a one time doorway into the Kingdom, it is a steady way of walking with Him in the light every day, because in the Lord’s Prayer He teaches born again disciples to keep praying, “forgive us our debts,” in the present tense, as a normal part of daily life, not as an old beginner prayer we leave behind. Jesus ties this ongoing confession to our fellowship with the Father, since He adds, “as we also have forgiven our debtors,” which means He expects a living rhythm of confessing sin and releasing others, almost like breathing in mercy and breathing it back out.

In John 13, when Peter resists the foot washing, Jesus tells him, “Those who have had a bath need only to wash their feet,” which shows this pattern so clearly, the “bath” is that once for all cleansing of new birth, but the “feet” pick up dust from daily sin, so we come again and again for fresh washing, not to get saved again, but to walk clean and close.

Jesus also tells the church in Revelation 3:19, “Be zealous therefore, and repent,” speaking to people who already know Him, which means regular confession is part of normal Christian life, not a rare emergency move when we fall in some huge public way. Many of us like the idea of being forgiven once, but we resist the humbling practice of confessing often, yet Jesus keeps putting it in front of us as a gift, not as a shame trap, because He knows our hearts harden when we hide and soften when we bring our sin into His light.

The apostle John, who walked with Jesus, reflects this when he writes, “If we confess our sins, He is faithful and just to forgive us our sins and to cleanse us from all unrighteousness,” and the Greek verb for “confess” there points to an ongoing habit, not a one time event, something that fits the daily “forgive us” that Jesus taught. In real life, that means you do not wait for Sunday or some crisis, you talk to God quickly and plainly whenever the Holy Spirit puts His finger on something, even if it feels small, because repeated “small” sins, left unspoken, add up like plaque on the heart.

Confession keeps the relationship honest, like keeping a window clean so the light can pour in, and Jesus is never tired of hearing the same kind of sin brought to Him for the thousandth time, He is tired of us pretending we do not need His Blood anymore. Regular confession is not spiritual anxiety, it is spiritual honesty, and as you make it a habit, you start to notice that the Holy Spirit is quicker to convict and your heart is quicker to respond, which is a sign of health, not failure.

If you want a simple way to practice this with Scripture and prayer, this resource on Biblical confession practices can help you build a daily rhythm that matches what Jesus taught. So when you think about confession, do not picture a one time doorway you walked through years ago, picture a path you keep walking with Jesus, where every honest “Lord, I did this, it was sin, please forgive me,” becomes another step in real friendship with the One who already knows you and still chose the cross for you.

“His Word Is Not In Us”: Logos, Jesus As The Word Of God, And A Hollow Religious Life

In 1 John 1:10, John writes that if we say we have not sinned, “His Word is not in us.”

Logos means word, message, or explanation. In John’s Gospel, it goes even deeper. In John 1:1, “In the beginning was the Word (Logos).” In 1:14, “The Word became flesh and lived among us.” Logos is a title for Jesus Himself.

So when John says “His Word is not in us,” two layers are present:

• The written Word has no real home in us. We may quote it, but we do not bow to it.
• The living Word, Jesus, is not inside, ruling and shaping us.

Think of a church leader who preaches strong sermons against certain sins, but quietly abuses money or people. They use the Bible, but they do not let the Bible use them. They quote the Word, but the Word is not actually in them.

This theme leads straight toward Matthew 7:21-23, where Jesus talks about people who prophesy and work miracles in His Name but still hear Him say, “I never knew you.”

---

Is God Inside Someone Who Keeps Choosing Sin Over Him?

Here is the tension.

On one side, verses like 1 John 3, James 2, and Matthew 7 say that a life given over to sin shows that someone does not truly know God.

On the other side, Romans 7, 1 John 2:1-2, and Galatians 6 show that real believers still stumble, sometimes in long battles.

We need a simple line:

• Stumbling in sin: you fall, you grieve, you confess, you fight.
• Surrendering to sin: you live in it, defend it, excuse it, and refuse the light.

God is not inside the person who will not choose God over sin and lives in steady denial. He may be in their songs and on their bumper stickers, but not in their heart.

However, a true believer who grieves, confesses, and keeps coming back, even after many falls, does have God living in them. The war itself is a sign of life.

This is where the idea of a reprobate mind, especially in certain areas, starts to show up.

What The Bible Says About God Living Inside A Person

Here are some core verses:

• John 14:23: Jesus says that the Father and Son will “make our home” with the one who loves Him and keeps His Word.
• Romans 8:9-11: Anyone who does not have the Spirit of Christ does not belong to Him, but those who do have the Spirit have life.
• 1 Corinthians 3:16 and 6:19: Believers are God’s temple, the Spirit lives in them.
• 1 John 3:24: We know He lives in us by the Spirit He gave us.

God living in us is not just about a prayer we once prayed. It shows up in growing obedience.

Picture your life as a house. Some people rent a “Sunday room” to Jesus. He can decorate that room. The rest of the house is off limits. Others hand Him the whole house, even if it is messy. He is not a renter there. He is the owner.

Constant, stubborn sin against clear light does not match a house where Jesus truly owns the keys.

How Choosing Sin Over God Shows What We Really Love

James 1:14-15 says that desire gives birth to sin, and sin grows up and brings death.

1 John 2:15-17 says we must not love the world or its cravings more than God.

Every time we choose, we reveal what we love most. When someone keeps choosing a sin with no real fight, no confession, and no sorrow, it is a sign that their first love is not Jesus.

Think of:

• A business person who keeps cheating, lying on reports, and never repents, because “this is how you win.”
• A believer who controls their public image but refuses to forgive an ex or a parent, year after year.
• A person who stays in a sexual relationship they know is outside God’s plan, and builds a whole story about why God “understands.”

The problem is less about the number of falls and more about the direction of the heart. Repeated choice plus denial grieves and quenches the Holy Spirit.

The Role Of Confession And Walking In The Light For Those Who Still Struggle

In 1 John 1:7-9, “walking in the light” means honesty with God and others. It is not sinless perfection. It is open doors and clean windows.

Picture two sick people.

One keeps going to the doctor, admits the symptoms, takes the medicine, and asks for help. They are still sick, but they are moving toward health.

The other hides the sickness, throws away the medicine, and insists, “I am fine,” even as they get worse.

If you hate your sin, bring it into the light, and want to change, that is a strong sign that The Truth and The Word are working inside you, even if the battle is intense.

---

What Is A Reprobate Mind? Can Believers Become Hard In Certain Sins?

Romans 1:28 mentions a “debased” or “reprobate” mind. The Greek phrase is adokimos nous.

• Adokimos means “rejected after testing,” not approved.
• Nous means “mind” or “way of thinking.”

Romans 1 describes people who knew something of God but refused to honor him. They loved sin more than truth. So God “gave them over” to their own desires.

Key steps in Romans 1:

1. They knew God but did not honor or thank him.
2. Their thinking became empty.
3. Their hearts were dark.
4. They traded God’s truth (alētheia) for lies.
5. God gave them over to those desires.

A reprobate mind is what happens after many firm “no’s” to God. It is a mind that has been tested and, after long refusal, is given over.

Helpful summaries of this idea can be found in resources like What does it mean to have a reprobate mind? and Where Does the Bible Mention the Reprobate Mind?.

The question we are asking here is very sharp:
Can a believer become reprobate in some areas of sin, yet still act righteous in other parts of life?

Biblical Meaning Of A “Reprobate Mind” (Adokimos Nous) In Romans 1

We already touched the meaning, but notice the outcome.

People once felt guilt about their sin. Over time, that guilt fades. They might even start to brag about what they once hid.

For example:

• A person once felt shame after adultery. Over years, they now boast about their “freedom” and “finding their true self.”
• Someone used to feel sick after cheating people in business. Now they laugh about how “smart” they are to get ahead.

They have traded truth for lies. In terms of 1 John, “the truth is not in them.” The light is almost gone.

How Ongoing Sin Can Harden Specific Parts Of A Believer’s Mind

The Bible also talks about hardening in people who are around God’s people.

Hebrews 3:13 warns us not to be “hardened by the deceitfulness of sin.”
Ephesians 4:17-19 speaks of “futility of mind,” darkened understanding, and hearts that lose sensitivity.

It seems that people, even in the church, can grow dull and blind in certain areas if they keep saying “no” to God there.

Examples:

• A pastor who is faithful to their spouse and clear in doctrine, but deeply proud and greedy. They explain away their love of money as “God’s blessing” and feel no check.
• A believer who avoids sexual sin and serves in church, but holds to racist attitudes or deep hatred toward a group, and calls it “just how I was raised.”

Their conscience in that one area has been “seared” (1 Timothy 4:2), burned like with a hot iron, while other parts of life still respond to God.

This is not normal Christian life. It is dangerous. But it shows that partial hardness is possible.

Can A Person With A Reprobate Area Still Be Saved?

We should tread with care, but Scripture gives some help.

• 1 Corinthians 3:15 speaks of someone whose work is burned up, but “he himself will be saved, but only as through fire.”
• Hebrews 12:5-11 describes God’s hard discipline for His true children, sometimes very painful, yet given in love.
• 1 John 5:16-17 speaks of “sin not leading to death” and “sin leading to death,” and does not spell out every detail. It warns us without satisfying our curiosity.

God may allow heavy discipline, even sickness or early death, to a believer who refuses to turn from stubborn sin. That does not always mean they were never saved. It does mean God takes holiness very seriously.

If you are worried that your mind is reprobate, that worry is often a sign your heart is not fully hardened yet. The door is still open. The call is to repent, not to sit in fear with no hope.

---

Are The People In Matthew 7:21-23 Just Religious Or Truly Reborn?

Matthew 7:21-23 is one of the most sobering texts in the Bible.

Jesus says that not everyone who calls Him “Lord” will enter the Kingdom, but only those who do the will of His Father. Some will say, “We prophesied, cast out demons, and did mighty works in your name.” Jesus will answer, “I never knew you. Depart from me, you who practice lawlessness.”

The word for “lawlessness” is anomia. It means living as if God’s law does not matter, as if His commands do not apply.

If you want to see more about anomia, a simple overview is in Anomia: A State of Lawlessness.

These people in Matthew 7 are not weak believers who hate their sin and fight it. They are people who lived in lawlessness while using the name of Jesus as a kind of badge.

Their core was never yielded to Him.

“I Never Knew You”: What Jesus Meant In Matthew 7:21-23

Notice the word “never.”

Jesus does not say, “I knew you for a while, then you drifted.” He says, “I never knew you.”

“Knew” here is relational. In John 10, Jesus says He knows His sheep and they know His voice. This is close, real relationship.

So you can have:

• Miracles.
• Prophecy.
• Public ministry.

And still not have Jesus living in you.

The key sign that He does live in you is not power. It is relationship and obedience. This matches 1 John: those who walk in the light, confess sin, and obey show that they truly know Him.

Religious Activity Without Jesus In Us: Modern Examples And Warnings

Modern life has many Matthew 7 pictures.

• A pastor who preaches against sin but secretly controls, abuses, or steals.
• A worship leader with amazing gifts who lives in hidden sexual sin and never truly repents.
• A believer who attends every meeting, speaks fluent Christian language, but refuses to let go of hatred or racism, year after year.

The problem is not that they fail sometimes. We all do. The danger is a settled pattern of sin that they defend as normal or even right.

2 Timothy 3:5 describes people who have “a form of godliness but deny its power.” They look spiritual, but they will not let the power of God change their actual lives.

Such people may look more like Matthew 7 (never truly known by Jesus) than Romans 7 (a believer in deep struggle).

How To Tell The Difference Between A Weak Believer And A Fake Religious Life

Here are simple heart questions you can ask:

• Do I grieve over my sin, or do I only fear getting caught?
• Do I bring my sin into the light, or do I hide and defend it?
• Do I want Jesus more than I want my sin?
• Is there any area where I refuse to let God speak or change me?

1 John gives some tests:

• Do I believe in the real Jesus?
• Do I love other believers?
• Do I keep God’s commands as my pattern of life?
• Do I confess my sin, or do I claim to be fine?

A weak believer may fall, even many times, but they keep crawling back to Jesus and never call evil good.

A fake religious life protects sin, hides it, and uses religion as a mask.

Ask the Holy Spirit to search your heart. He is kind, but He is honest.

---

Walking Out Of Darkness: How To Turn From Sin And Invite The Word And Truth To Rule In You

Let us come back to where we started.

1 John 1:9 is a doorway. Honest confession leads to real cleansing and restored fellowship. No matter how many times you have fallen, the door is still open if your heart is still willing to turn.

Here is a simple path that lines up with what we have seen:

• Honest confession.
• Real turning from sin.
• Inviting the Holy Spirit to renew your mind.
• Seeking help from trusted believers.
• Building habits that feed truth instead of darkness.

If you want to grow in knowing the Spirit’s work, teaching about the baptism of the Holy Spirit can help you understand how God fills and empowers His people for holy living.

Jesus, the Word and the Truth, is not stingy. He gladly lives inside anyone who comes with empty hands and a real “yes,” even if that “yes” is trembling.

Honest Confession: Agreeing With God About Specific Sin

Here is what confession that matches homologeō looks like:

1. Name the sin clearly. Not “I messed up,” but “I lied,” “I slept with someone I am not married to,” “I watched porn,” “I held on to hatred.”
2. Agree with God that it is sin. You do not excuse it or blame others.
3. Ask for cleansing. “Wash me. Change me. I cannot clean myself.”
4. Bring someone trusted in when needed. James 5:16 tells us to confess to one another and pray so that we may be healed.

Examples of simple prayers:

• “Father, I confess that I have chosen porn over you. I agree that it is sin. Wash me and change my mind.”
• “God, I agree that my bitterness toward this person is sin. I choose to forgive and ask you to heal my heart.”

Real confession also includes real steps to cut off access to temptation.

Choosing New Paths: Repentance, Boundaries, And Renewing The Mind

Repentance in Greek is metanoia, a change of mind that leads to a change of direction.

Some practical steps:

• Install filters or delete apps that make sin easy.
• Change friend groups if they keep pulling you into old patterns.
• Seek counseling or pastoral care for deep wounds behind certain sins.
• Memorize verses that speak right to your battle, like 1 Corinthians 10:13 or 2 Timothy 2:22.
• Build new habits that feed your spirit, like prayer, Scripture, and serving others.

Romans 12:2 talks about being “transformed by the renewing of your mind.” Ephesians 4:22-24 tells us to “put off” the old self, “be renewed,” and “put on” the new.

Repeated right choices with God’s help can slowly rewrite the thinking behind a reprobate area. The same mind that once loved sin can learn to love holiness.

Living As A Temple Of God: Letting Jesus Rule Every Room In Your Life

You are a temple, not a shed. God wants to live in you, not just visit.

Picture your life as a house with many rooms:

• Money
• Sex
• Family
• Work
• Church
• Secret thoughts
• Past wounds

Ask yourself: “Is there any room where I have told Jesus, ‘You cannot come in here’?”

Invite Him in, room by room. Honest, sometimes painful light will come. But with that light comes healing.

A simple prayer might be:

“Lord Jesus, you are the Word and the Truth. I open every room of my life to you. Show me any sin I have loved or defended. I agree with you about it. Cleanse me. Rule in me. Fill me with your Spirit. I want you more than I want my sin.”

---

Conclusion: Let The Word And The Truth Live In You

We have seen that, in the Greek of 1 John 1:8-10, denying sin proves that The Truth and The Word are not in us. Confessing sin, on the other hand, shows that we are walking in the light and being cleansed by God.

Jesus is both the Truth and the Word. He does not live in a heart that clings to sin with no repentance, even if that heart is full of religious activity. Yet real believers can still be weak and even hardened in some areas if they keep saying yes to sin and no to His voice.

Romans 1 describes a full reprobate mind that God has given over. Some believers may taste a smaller version of that in specific areas when they refuse God’s light, even while they still belong to Christ. Matthew 7:21-23 warns us about religious workers who never truly knew Jesus at all, even while using His name.

The hope is simple and strong: anyone who turns from sin and comes to Jesus in faith can have the Word and the Truth living inside them. Keep asking Him to search you, keep confessing, keep trusting His promise that He is faithful and just to forgive and to cleanse. And keep seeking teaching and fellowship that help you love God more than your sin, one honest step at a time.

Read more about  a reprobate mind here: